Fuel pump per the link above.
06 Cruiser, P0430 fixed (1 Viewer)
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- Thread starter
- #22
Another update-
I went through the the plugs and coils today. The coils looked good, although I did put a tear in the end of one of the rubber boots when trying to retrieve a loosened spark plug. Rookie mistake. Should have just used the magnet as I did after the mishap. Anybody know if I can find a replacement boot? Or maybe just leave it?
The plugs were dirty and cleaned via the Harbor Freight spark plug cleaner referenced by LC2001 (thanks for the suggestion). Truck seemed a bit smoother, especially at idle, after the cleaning but nothing drastic.
To Nav07, I am no expert but from the research I’ve done, and speaking with my mechanic friend, your issue, and mine could be caused by vapor lock, which to my understanding occurs when the gasoline gets so hot it boils before combustion in the cylinder. I understand that this can be caused by a malfunctioning fuel pump, for example, which causes the fuel to heat up, though would not cause the engine temp. to increase. That is why your engine temp. gauge would read normal. Waiting 20-30 mins. after stalling allows the fuel/ fuel pump to cool, and you’re off and running again. This fits with the symptoms reported by the prior owner of the white ‘06 restored by LC2001.
Due to the cost of the Catalytic Converter replacement, I will not go that route unless I am certain that is my issue. Since clearing the P0430 code, I have made it a point to drive it hard, including freeway and street driving. So far no issues, no codes. This leads me to believe that the issue is not with the Cats. and that the code that was thrown was a residual from my original problem which seems to fit with the “bad fuel pump” explanation.
I’ll do some more research/inspection on the charcoal canister tomorrow but I’m leaning more and more toward the fuel pump being the culprit. If nothing else, it’s certainly a cheaper starting point than replacement of the Cat.
You’re up to date for now. As always, any feedback/corrections of mythodology or errors in assumption are greatly appreciated. As I mentioned before, I’m an amateur at best and would much rather be shown I’m wrong, than to mistakenly believe I am right- Dave.
I went through the the plugs and coils today. The coils looked good, although I did put a tear in the end of one of the rubber boots when trying to retrieve a loosened spark plug. Rookie mistake. Should have just used the magnet as I did after the mishap. Anybody know if I can find a replacement boot? Or maybe just leave it?
The plugs were dirty and cleaned via the Harbor Freight spark plug cleaner referenced by LC2001 (thanks for the suggestion). Truck seemed a bit smoother, especially at idle, after the cleaning but nothing drastic.
To Nav07, I am no expert but from the research I’ve done, and speaking with my mechanic friend, your issue, and mine could be caused by vapor lock, which to my understanding occurs when the gasoline gets so hot it boils before combustion in the cylinder. I understand that this can be caused by a malfunctioning fuel pump, for example, which causes the fuel to heat up, though would not cause the engine temp. to increase. That is why your engine temp. gauge would read normal. Waiting 20-30 mins. after stalling allows the fuel/ fuel pump to cool, and you’re off and running again. This fits with the symptoms reported by the prior owner of the white ‘06 restored by LC2001.
Due to the cost of the Catalytic Converter replacement, I will not go that route unless I am certain that is my issue. Since clearing the P0430 code, I have made it a point to drive it hard, including freeway and street driving. So far no issues, no codes. This leads me to believe that the issue is not with the Cats. and that the code that was thrown was a residual from my original problem which seems to fit with the “bad fuel pump” explanation.
I’ll do some more research/inspection on the charcoal canister tomorrow but I’m leaning more and more toward the fuel pump being the culprit. If nothing else, it’s certainly a cheaper starting point than replacement of the Cat.
You’re up to date for now. As always, any feedback/corrections of mythodology or errors in assumption are greatly appreciated. As I mentioned before, I’m an amateur at best and would much rather be shown I’m wrong, than to mistakenly believe I am right- Dave.
Denso does make a replacement boot for coils, others may also. Boots break easy if coil(s) been running hot, they get brittle. A loose spark plug or wide gap can be at fault for increased heat.
I'm curious, did any of the spark plugs seem loose while removing?
What was the gap of the spark plugs?
Did you torque the spark plug to 13ft-lbf?
Fuel pump (FP) issue of the 06 is a mystery. We don't no why sometimes replacing it solves the issue of ascending to high altitude stall, as FP usually test as good. We also don't know if Snowy's PO overfilled the gas tank, in that example.
We do know you overfilled the gas tank, which "may" have damage the charcoal canister or associated valves. Give it some time now to see how it does, now that you've stop overfilling.
IIRC, FSM states to check for exhaust leak, then A/F (front O2) & O2 (rear) then CAT with a P0430. A loose spark plugs can be consider and exhaust leak. Typical exhaust leak you'll hear a tick that speed up with RPM, often going away once engine warmed up.
Assuming your engine is well tuned (a must), this includes no vacuum or exhaust leaks. I'd run a can of Cat Cleaner through the gas tank. Make sure to get out and drive at High RPM around 4,500 RPM (good oil a must) for 5 to 7 minutes. Do it a few times as you finish with tank of Cat Cleaner mix and start of a fresh tank of gas. Clear code and see if it returns.
If P0430 returns I'd focus on O2's first, CAT's second.
I'm curious, did any of the spark plugs seem loose while removing?
What was the gap of the spark plugs?
Did you torque the spark plug to 13ft-lbf?
Fuel pump (FP) issue of the 06 is a mystery. We don't no why sometimes replacing it solves the issue of ascending to high altitude stall, as FP usually test as good. We also don't know if Snowy's PO overfilled the gas tank, in that example.
We do know you overfilled the gas tank, which "may" have damage the charcoal canister or associated valves. Give it some time now to see how it does, now that you've stop overfilling.
IIRC, FSM states to check for exhaust leak, then A/F (front O2) & O2 (rear) then CAT with a P0430. A loose spark plugs can be consider and exhaust leak. Typical exhaust leak you'll hear a tick that speed up with RPM, often going away once engine warmed up.
Assuming your engine is well tuned (a must), this includes no vacuum or exhaust leaks. I'd run a can of Cat Cleaner through the gas tank. Make sure to get out and drive at High RPM around 4,500 RPM (good oil a must) for 5 to 7 minutes. Do it a few times as you finish with tank of Cat Cleaner mix and start of a fresh tank of gas. Clear code and see if it returns.
If P0430 returns I'd focus on O2's first, CAT's second.
I have got to add, nothing cleans a Cat, this stuff is mis-sold, it can help by cleaning the fuel system but not the CAT itself. Over time the Cats lose efficiency as the precious metals get sent out of the exhaust. If you can get a smog test and have the CO reading this can tell you if the CAT is efficient or if the downstream oxy sensor is telling lies and is off slightly. Now the easiest way to see is if the downstream oxy voltage is fluctuating up and down like a upstream 02 signal, this means the CAT is having no effect on the exhaust gases as it should, as if it did it will hold the voltage steady at idle.
A fuel pump issue will cause premature failure of a CAT and not repair one that has already suffered.
If the fuel mixture is rich or lean the downstream oxy sensor should still hold steady just that the voltage will be low or high.
Another issue is that the sensors can be slow to respond, this normally flags up a fault after the initial warming up of the engine and when the fuel system goes closed loop. So this means the 02 sensors are monitored but not performing in the range that they should, but this can improve with more heat so when you read the signals when hot they look fine and the engine runs ok. It is as if the heating element in the sensor has lost efficiency.
The reason for so many CAT failures for this year of truck might not have anything to do with the engine or the CAT itself, it might be that your emmision laws had or was about to change and that the monitoring software was programmed to be more strict and more sensitive to CAT efficiency, so this reduces the lifespan of a usable CAT on your car. I had two non efficient CATs that I changed, this didn’t produce a CEL as the law in the UK didn’t require the CAT efficiency to be monitored in 1998, but this changed in 2005 when euro4 emmisions was the standard.
A fuel pump issue will cause premature failure of a CAT and not repair one that has already suffered.
If the fuel mixture is rich or lean the downstream oxy sensor should still hold steady just that the voltage will be low or high.
Another issue is that the sensors can be slow to respond, this normally flags up a fault after the initial warming up of the engine and when the fuel system goes closed loop. So this means the 02 sensors are monitored but not performing in the range that they should, but this can improve with more heat so when you read the signals when hot they look fine and the engine runs ok. It is as if the heating element in the sensor has lost efficiency.
The reason for so many CAT failures for this year of truck might not have anything to do with the engine or the CAT itself, it might be that your emmision laws had or was about to change and that the monitoring software was programmed to be more strict and more sensitive to CAT efficiency, so this reduces the lifespan of a usable CAT on your car. I had two non efficient CATs that I changed, this didn’t produce a CEL as the law in the UK didn’t require the CAT efficiency to be monitored in 1998, but this changed in 2005 when euro4 emmisions was the standard.
BG has a product line that I trust and have been using for many years, it's the number #1 used in Colorado shops. I only recently learned it is not available everywhere.
Here's what they have to say about CAT and O2 cleaning:
"BG 44K® is 11 ounces of high quality detergents and additives that you pour right into the gas tank to restore performance and gas mileage. It removes carbon from combustion chambers, intake manifolds, ports and on valves and restores flow in fuel injectors. Also proven to clean oxygen sensors and catalytic converters. Basically, it cleans the entire fuel system!"
I like to run at RPM for short periods (~5min) once done with a fuel tank mixed with cleaner. The reason I do this; I assume the cleaner has done its job and washed out or loosened the varish, crud and carbon from the fuel and combustion system. Running engine hard forces fuel system to run at highest pressure, helping to wash out rements. It also causes combustion chamber to run at it highest pressure and hottest, blowing out and "cooking off" what cleaners have loosened.
This "cooking off" (run at high RPM) also runs CAT at higher pressures and temperature then normal lite driving would. This is believed to cook-off gunk that may have built up on elements of CAT(s). It's like turning one's oven to clean mode (is the premises) turning rements to ash and blowing it out the tailpipe.
I know this works very well for the fuels system and combustion chamber, based on before & after inspection/pictures/results. I can't say I know this for the CATs & O2s, as I've not ever seen before and after, it is a presumption. But the idea here is to make sure we give CAT(s) and O2(s) the best chance with purest test we can. Most shop are not going to do this first or recommend it, it's just not cost effective.
I agree @Julian Stead, if CAT is bad it's bad and replacement is only cure to get back to factory spec.
Here's what they have to say about CAT and O2 cleaning:
"BG 44K® is 11 ounces of high quality detergents and additives that you pour right into the gas tank to restore performance and gas mileage. It removes carbon from combustion chambers, intake manifolds, ports and on valves and restores flow in fuel injectors. Also proven to clean oxygen sensors and catalytic converters. Basically, it cleans the entire fuel system!"
I like to run at RPM for short periods (~5min) once done with a fuel tank mixed with cleaner. The reason I do this; I assume the cleaner has done its job and washed out or loosened the varish, crud and carbon from the fuel and combustion system. Running engine hard forces fuel system to run at highest pressure, helping to wash out rements. It also causes combustion chamber to run at it highest pressure and hottest, blowing out and "cooking off" what cleaners have loosened.
This "cooking off" (run at high RPM) also runs CAT at higher pressures and temperature then normal lite driving would. This is believed to cook-off gunk that may have built up on elements of CAT(s). It's like turning one's oven to clean mode (is the premises) turning rements to ash and blowing it out the tailpipe.
I know this works very well for the fuels system and combustion chamber, based on before & after inspection/pictures/results. I can't say I know this for the CATs & O2s, as I've not ever seen before and after, it is a presumption. But the idea here is to make sure we give CAT(s) and O2(s) the best chance with purest test we can. Most shop are not going to do this first or recommend it, it's just not cost effective.
I agree @Julian Stead, if CAT is bad it's bad and replacement is only cure to get back to factory spec.
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If you ever see the pictures off the Cat cleaner adverts, they show photo’s of a obviously neglected engine, the carbon build up is extreme.
For a well maintained vehicle fuel additives are good to help clean the injectors and remove water from the fuel tank as the gas put in vehicles is of a unknown standard of quality.
Easiest and most effective way to stop carbon build up is regular oil changes. Most pollution into the engine comes from the crankcase, now if you have foul contaminated aged oil this can reek havoc in producing sticky blacky carbon through the pcv system and through the inlet and all the way out to the exhaust. The solution is a oil change plus then a fuel cleaner can help clean up this mess. Now for a well maintained engine this doesn’t require this same treatment as it doesn’t get to the same state.
When we wanted to start selling fuel additive as part of the scheduled service we had to ask the car manufacturer for their permission. They agreed but had to sell a cleaner that didn’t say it cleaned CAT’s, O2 sensors and such as it is would be mis selling. We was allowed to sell Forte fuel cleaner as it only says that it cleans the fuel system and can help keep the engine running efficiently. We wasn’t allowed to sell it for any kind of repair or to try and improve a poorly running vehicle or one that has emmision issues as the manufacturer said again that it is mis selling. Plus it was never to be used as part of any warranty claim or part of a repair associated with something the fuel cleaner/ cat cleaner claimed as it has never been proven to actually repair anything.
The difference with putting it in a car coming in for repair to one that runs ok is totally different. If a car comes in with a faulty 02 sensor and is running rough, no amount of fuel cleaner fixes it.
Diesel cars are a bit different as carbon build up is more of an issue, as these engines foul up there engine oil and egr systems pretty quickly. But again a strict oil maintenance helps more than a fuel cleaner.
I use a fuel cleaner once a year and give it a blast down the road to help clean the system, but I would never associate it as part of a repair procedure. If You have excessive carbon build up then you are better off finding out why.
For a well maintained vehicle fuel additives are good to help clean the injectors and remove water from the fuel tank as the gas put in vehicles is of a unknown standard of quality.
Easiest and most effective way to stop carbon build up is regular oil changes. Most pollution into the engine comes from the crankcase, now if you have foul contaminated aged oil this can reek havoc in producing sticky blacky carbon through the pcv system and through the inlet and all the way out to the exhaust. The solution is a oil change plus then a fuel cleaner can help clean up this mess. Now for a well maintained engine this doesn’t require this same treatment as it doesn’t get to the same state.
When we wanted to start selling fuel additive as part of the scheduled service we had to ask the car manufacturer for their permission. They agreed but had to sell a cleaner that didn’t say it cleaned CAT’s, O2 sensors and such as it is would be mis selling. We was allowed to sell Forte fuel cleaner as it only says that it cleans the fuel system and can help keep the engine running efficiently. We wasn’t allowed to sell it for any kind of repair or to try and improve a poorly running vehicle or one that has emmision issues as the manufacturer said again that it is mis selling. Plus it was never to be used as part of any warranty claim or part of a repair associated with something the fuel cleaner/ cat cleaner claimed as it has never been proven to actually repair anything.
The difference with putting it in a car coming in for repair to one that runs ok is totally different. If a car comes in with a faulty 02 sensor and is running rough, no amount of fuel cleaner fixes it.
Diesel cars are a bit different as carbon build up is more of an issue, as these engines foul up there engine oil and egr systems pretty quickly. But again a strict oil maintenance helps more than a fuel cleaner.
I use a fuel cleaner once a year and give it a blast down the road to help clean the system, but I would never associate it as part of a repair procedure. If You have excessive carbon build up then you are better off finding out why.
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That video is how they flush out diesel particle filters. A Diesel particle filter over time clogs up with their additive, this additive is added into the diesel every time you fill up the fuel tank and is a serviceable item as is a particle filter, the particle filter needs to be cleaned out with water in this way but in reality all you do is buy a exchange unit. When you go to the parts department at your dealership and buy a exchange unit, all it is you buy is a unit that has been treated in this way. It is crazy the price of them after all they have only been cleaned out and not made from new. This is a dealership scam in my opinion, I don’t buy diesel cars but a friend used to use a pressure washer with some degreaser chemical and got some pretty good results.
Ps. The dealership doesn’t clean them, they are cleaned by the manufacturer.
Ps. The dealership doesn’t clean them, they are cleaned by the manufacturer.
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I'm rooting around for a good way to clean a set of CATs off the rig. I'm concerned coolant may have gotten in, so I'd like to flush them before running engine. I know coolant is a CAT killer, but IDK if coolant just getting on/in or needs heat added to mix to kill.
It doesn’t kill them instantly, it is that coolant blocks them up over time. When coolant evaporates it leaves a residue that will carbon up in the CAT. You see this residue when you get a leak around the engine and it is heated to evaporation.
- Thread starter
- #32
Another update-
The boot on the ignition coil which I cracked by trying to press it onto the loosened spark plug in order to retrieve the spark plug did cause an issue. The result of the cracked boot was a misfire that would sometimes throw a code, and sometimes not throw a code. In trying to diagnose the misfire I first replaced all spark plugs with new ones, not feeling confident in my spark plug cleaning/gap checking of the old plugs.
When the misfire continued I ordered a new ignition coil and replaced the coil that had the cracked boot. This cured the misfire issue, though the P0430 code and check engine light remained. I then ordered some replacement boots. Though I searched their website, and the websites of authorized Denso dealers, I could not find Denso factory replacement boots for this coil, though I did find replacement boots for other Denso ignition coils. I ended up buying some on Amazon that were made to fit the 2uz-fe coils. They were sold as "Coil over plug boot" for those that are interested in trying to find replacements. Once I had the replacement boots, I replaced the torn boot on my old ignition coil, put it back in place of the brand new coil, and the truck ran fine. Hence I now have a brand new, spare ignition coil that will ride in my tool/travel kit.
After fixing the misfire issue I have not had time to get back to the P0430 issue, other than researching a bunch of threads on the P0430 and P0420 issue. FYI there's a lot of good info on this site for others with these codes.
After reading through those threads I started gathering parts- new fuel filter, new thermostat/thermostat gasket and Toyota factory coolant, new pcv valve, and new intake manifold gaskets, planning on tackling those issues today, 2-21. In the meanwhile, I've been driving around w/ the check engine, vsc, and trac lights on for the last couple weeks.
However last night, I put a bottle of Chevron fuel system cleaner, $9.99, into the gas tank which was about 3/8 full. I then drove my boys to baseball practice and back (which is maybe 3-4 miles each way). Coming home last night from baseball practice, the dash lights were still on. When I started up the truck this morning, ready to head to my buddy's shop w/ my new parts, there were no indicator lights on the dash. They remained off all day. I went ahead and replaced the fuel filter, thermostat, and pcv valve anyway and the CEL light remained off after the new parts were put on. I did not get to the intake manifold gaskets, but I'm not sure that they need replacing, as there is no sign of oil seepage on the lower portions of the manifold (thanks to LC2001 to look out for this issue w/ vvti engines).
You're up to date for now. Thanks to all who have responded to my questions, and contributed to threads by others w/ similar issues.
The boot on the ignition coil which I cracked by trying to press it onto the loosened spark plug in order to retrieve the spark plug did cause an issue. The result of the cracked boot was a misfire that would sometimes throw a code, and sometimes not throw a code. In trying to diagnose the misfire I first replaced all spark plugs with new ones, not feeling confident in my spark plug cleaning/gap checking of the old plugs.
When the misfire continued I ordered a new ignition coil and replaced the coil that had the cracked boot. This cured the misfire issue, though the P0430 code and check engine light remained. I then ordered some replacement boots. Though I searched their website, and the websites of authorized Denso dealers, I could not find Denso factory replacement boots for this coil, though I did find replacement boots for other Denso ignition coils. I ended up buying some on Amazon that were made to fit the 2uz-fe coils. They were sold as "Coil over plug boot" for those that are interested in trying to find replacements. Once I had the replacement boots, I replaced the torn boot on my old ignition coil, put it back in place of the brand new coil, and the truck ran fine. Hence I now have a brand new, spare ignition coil that will ride in my tool/travel kit.
After fixing the misfire issue I have not had time to get back to the P0430 issue, other than researching a bunch of threads on the P0430 and P0420 issue. FYI there's a lot of good info on this site for others with these codes.
After reading through those threads I started gathering parts- new fuel filter, new thermostat/thermostat gasket and Toyota factory coolant, new pcv valve, and new intake manifold gaskets, planning on tackling those issues today, 2-21. In the meanwhile, I've been driving around w/ the check engine, vsc, and trac lights on for the last couple weeks.
However last night, I put a bottle of Chevron fuel system cleaner, $9.99, into the gas tank which was about 3/8 full. I then drove my boys to baseball practice and back (which is maybe 3-4 miles each way). Coming home last night from baseball practice, the dash lights were still on. When I started up the truck this morning, ready to head to my buddy's shop w/ my new parts, there were no indicator lights on the dash. They remained off all day. I went ahead and replaced the fuel filter, thermostat, and pcv valve anyway and the CEL light remained off after the new parts were put on. I did not get to the intake manifold gaskets, but I'm not sure that they need replacing, as there is no sign of oil seepage on the lower portions of the manifold (thanks to LC2001 to look out for this issue w/ vvti engines).
You're up to date for now. Thanks to all who have responded to my questions, and contributed to threads by others w/ similar issues.
Thanks for the update. Nice call on the boots. Great overall tune up job!
I don't recall if you stated: did your spark plugs feel loose or not?
Recently pulling factory installed spark plugs on The Black Knight at 59K miles, finding them loose. I realized i'm finding a pattern of loose spark plugs. It's not just this one rig I found plugs loose, but many at vary miles. Inside plugs (3, 5, 4, 6) I most often found loose. It's these plugs I most often find hallos/Corona's on too.
I was looking at these plugs as compression leakage of defective plug. This was especially true when I was striation, like jet plumes. I'm now thinking it has more to do with combustion gases leaking passed the threat due of loose plugs. This would also overheat boots and dry it out, before their time.
I am now convinced we've and issues with spark plugs loosening. For this reason I've added checking spark plugs at 30K miles as a PM.
This aren't are plugs, but represent what I'm seeing. It seems to be the inside plugs that I see this on the most:
After all you've done, if P0430 comes back. Consider replacing the rear O2.
I still recommend a burn out drive (High RPM drive) near end and after gas tank with the fuel cleaning system additive. This helps blow out and remaining gunk & carbon. It also is believe to cook off CAT's and O2's of gunk.
I don't recall if you stated: did your spark plugs feel loose or not?
Recently pulling factory installed spark plugs on The Black Knight at 59K miles, finding them loose. I realized i'm finding a pattern of loose spark plugs. It's not just this one rig I found plugs loose, but many at vary miles. Inside plugs (3, 5, 4, 6) I most often found loose. It's these plugs I most often find hallos/Corona's on too.
I was looking at these plugs as compression leakage of defective plug. This was especially true when I was striation, like jet plumes. I'm now thinking it has more to do with combustion gases leaking passed the threat due of loose plugs. This would also overheat boots and dry it out, before their time.
I am now convinced we've and issues with spark plugs loosening. For this reason I've added checking spark plugs at 30K miles as a PM.
This aren't are plugs, but represent what I'm seeing. It seems to be the inside plugs that I see this on the most:
After all you've done, if P0430 comes back. Consider replacing the rear O2.
I still recommend a burn out drive (High RPM drive) near end and after gas tank with the fuel cleaning system additive. This helps blow out and remaining gunk & carbon. It also is believe to cook off CAT's and O2's of gunk.
2007 - *think* I fixed it. Reporting back here. I was consistently getting P0420 and P0430 codes. At least one time per tank of gas. Sometimes the codes would come in together and sometimes I’d get them separately. I would clear them and then watch them for any other symptoms.
Here’s what I did (in this order, checking each time for codes coming back).
1) cleaned MAF (did not see any visual dirt, water spots - but probably had never been cleaned before)
2) replaced air filter (was a little dusty but not bad)
3) replaced gas cap (I may have broken one of the white plastic pieces in the cap, not sure)
4) put in BG 44K to clean fuel system
* after all of these “cheap” fixes I was still getting both codes
5) installed downstream O2 sensor - codes/CEL did not clear on their own, so I cleared and they have not been back in ~500 miles of driving and 2 fill ups.
6) I went ahead and changed the upstream O2 sensors because I had them ordered and we are all OCD like that
The advice has been given here already, but if I had to do it all over again, I’d jump straight to replacing the O2 sensors (downstream first).
If had not fixed with O2, I would have done fuel pump/filter next, then a full Cat replacement (not sure if would have tried aftermarket or not to save $$).
Here are pics of the old downstream O2 sensors.
Here are the old upstream O2 sensors.
As you can see, the upstream were in better shape. Not sure if I needed to change them or not, but I did.
- Thread starter
- #35
2001LC- I didn't indicate, but now that you mention it some of the inside plugs, I don't remember which, were not loose per se, but were not as tight as the 1, 2, 7, and 8 plugs. As to discoloration on the ceramic portion of the plugs, I don't recall and I've since thrown them out. In hindsight, it would have been a good idea to keep and label the plugs, or at least take photos, to help note any patterns should issues arise in the future. My scientific methodology is certainly not on par with yours.
COGerding- In researching the P0430, P0420 issues, (especially in the 06-07 cruisers) I have come to the tentative conclusion that there is likely not a single cause in most of these cases. I think its likely that there are a number of minor issues with various components of the fuel and air delivery systems (ie- dirty air filter, MAF, throttle body, fuel pump not performing optimally, fuel filter not performing optimally, small leaks in vacuum, exhaust, and intake systems, thermostat, pcv valve, injectors, plugs and coils not performing optimally, old dirty and worn sensors, etc.) that when a sufficient combination of any of these conditions exists, it can throw these codes.
To me, this explains the variability in what finally made the codes go away from the various people whom have posted with these issues. Perhaps we too often think that the last issue we addressed before the code went away was the sole cause, when it might be that we resolved enough of the small, difficult to diagnose problems up to that point, that the last issue addressed finally helped bring the system into balance.
But this also means that just because the code went away, it does not mean that every component of these systems is working optimally. There might still be slight issues with various components, but still an insufficient number of problems of insufficient severity to be noticed.
In my case, though the code is gone, as so many have reported fuel pump issues w/ the 06 that I am left wondering whether I should go ahead and replace it, given my initial symptom of stalling after a hard mountain climb. I am leaning toward replacing it for peace of mind, to ensure that that component of my system will no longer be a variable. At least once a year, and sometimes twice, I drive the family from Socal to Seattle and Montana, through numerous mountain passes, and sometimes desolate highways far from any service stations.
If anybody thinks its foolish of me to go ahead the replace the fuel pump, let me know. I've got a couple of months to decide as our next Montana trip is several months away.
COGerding- In researching the P0430, P0420 issues, (especially in the 06-07 cruisers) I have come to the tentative conclusion that there is likely not a single cause in most of these cases. I think its likely that there are a number of minor issues with various components of the fuel and air delivery systems (ie- dirty air filter, MAF, throttle body, fuel pump not performing optimally, fuel filter not performing optimally, small leaks in vacuum, exhaust, and intake systems, thermostat, pcv valve, injectors, plugs and coils not performing optimally, old dirty and worn sensors, etc.) that when a sufficient combination of any of these conditions exists, it can throw these codes.
To me, this explains the variability in what finally made the codes go away from the various people whom have posted with these issues. Perhaps we too often think that the last issue we addressed before the code went away was the sole cause, when it might be that we resolved enough of the small, difficult to diagnose problems up to that point, that the last issue addressed finally helped bring the system into balance.
But this also means that just because the code went away, it does not mean that every component of these systems is working optimally. There might still be slight issues with various components, but still an insufficient number of problems of insufficient severity to be noticed.
In my case, though the code is gone, as so many have reported fuel pump issues w/ the 06 that I am left wondering whether I should go ahead and replace it, given my initial symptom of stalling after a hard mountain climb. I am leaning toward replacing it for peace of mind, to ensure that that component of my system will no longer be a variable. At least once a year, and sometimes twice, I drive the family from Socal to Seattle and Montana, through numerous mountain passes, and sometimes desolate highways far from any service stations.
If anybody thinks its foolish of me to go ahead the replace the fuel pump, let me know. I've got a couple of months to decide as our next Montana trip is several months away.
Very good and fair points that need to be considered by others with the same issues - the variability in the solution (or perceived solution) is tricky which is why I tried to outline my path. I have to say I do *feel* better now that I don’t have my dash lighting up
I’m with you on the fuel pump replacement dillemma - same boat, I’ve stalled a few times on hot days at altitude. Would like to be preventative if I can. Have you priced out fuel pump/filter costs? Lexus dealership quoted me $600-$700 iirc. About 3 hours labor and $250-$300 parts. I haven’t looked elsewhere yet - may try and tackle it myself.
I agree with everything you've said. Working through starting at air filter and working back is simplest and best. In the end, we've a better tuned rig.
It seem the VVt engine are highly tuned, and more susceptible to minor deviation than non vvt. Possible upstream is affecting the health of O2's as well. I feel even more strongly on this accord when both P0420 & P0430 are seen at same time.
@Julian Stead IIRC, suggested the 06-07 may also have setting of tigers tighter due to environment law changes. Very possible as well!
Some have just added extension to the O2's tricking the ECU, which I don't like that idea. But I certainly understand in some cases.
If you've no further issues, no reason to replace fuel pump. If you do replace just as PM; Don't buy from Lexus Dealer if cost is issue, try online at Toyota Dealers. It's the same part.
- Thread starter
- #38
In the next week or so I'll try and make the same drive where I first encountered the stalling problem. If nothing else, it will allow me to drive hard and get the cats good and hot. If the issue repeats, I'll for sure be replacing the fuel pump which I will try and do myself. I'm sure there are good write-ups here, though I haven't searched yet. Again, though I'm not very experienced, I have the good fortune to have access to my friend's shop with a lift, all the right tools, and his know-how should I get in over my head. Luckily, he does mostly custom work and restorations, all by word-of-mouth, and there is always room for me at his shop.
The cheapest source for factory Toyota parts that I have found, I saw here, on IH8Mud. It is a Toyota dealer and parts supplier in Norwalk, CA. Try parts.norwalktoyota.com. They list the fuel pump for $260.54. For what it's worth, you will likely get a different price quote if you call. When I called about ordering different parts, the price quoted was not the same as the online price. When I brought up the difference, the guy I was speaking with said I had to order online to get the discounted price.
Lastly, does anybody know if I can change my initial heading under which I started this thread. I would like to add "P0430" to the head line to help others searching this issue. I saw that there is a 13 page thread trending w/ the P0420, P0430 title, with a lot of us discussing the same issues. Perhaps comments from this thread could be added to the other thread?
The cheapest source for factory Toyota parts that I have found, I saw here, on IH8Mud. It is a Toyota dealer and parts supplier in Norwalk, CA. Try parts.norwalktoyota.com. They list the fuel pump for $260.54. For what it's worth, you will likely get a different price quote if you call. When I called about ordering different parts, the price quoted was not the same as the online price. When I brought up the difference, the guy I was speaking with said I had to order online to get the discounted price.
Lastly, does anybody know if I can change my initial heading under which I started this thread. I would like to add "P0430" to the head line to help others searching this issue. I saw that there is a 13 page thread trending w/ the P0420, P0430 title, with a lot of us discussing the same issues. Perhaps comments from this thread could be added to the other thread?
Look at top of opening post (OP) for edit button>
There is probably write up somewhere.
I drained a fuel tank which in which I pulled the fuel pump. You may find it helpful.
Draining Fuel form gas tank?
There is probably write up somewhere.
I drained a fuel tank which in which I pulled the fuel pump. You may find it helpful.
Draining Fuel form gas tank?
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- Thread starter
- #40
Well, I thought that was too good to be true. About a week after my CEL cleared, after adding a bottle of Chevron fuel system cleaner to the gas tank, the CEL returned w/ the same P0430 code. I tried swapping the rear O2 sensors today to see if my P0430 turned into a P0420, but I found that the wires on the driver side sensor are not long enough to reach the corresponding plug on the passenger side. I suppose this explains why Toyota lists 2 different part numbers for the 2 rear sensors, while the Denso number for each sensor is the same. I imagine that if one were to order a Denso replacement, it would include the wires which are long enough to reach the plug regardless of which side it was plugged in to. Each O2 sensor had a Toyota part number, the two sensors having a different Toyota number, and a Denso part number, both of which were the same.
So, I will be ordering a Denso rear O2 sensor, but not through Toyota. I will post back with results.
In the meantime, I replaced the heater Tees, now with 146,000 on the clock. What a PITA that was. It seemed like each of the hose clamps were positioned in such a manner as to discourage anybody from attempting their own service. I positioned the clamps so that they will be more accessible in the future. Both of the tees were broken, one was completely disintegrated. Thanks again to this site for all the shared knowledge.
So, I will be ordering a Denso rear O2 sensor, but not through Toyota. I will post back with results.
In the meantime, I replaced the heater Tees, now with 146,000 on the clock. What a PITA that was. It seemed like each of the hose clamps were positioned in such a manner as to discourage anybody from attempting their own service. I positioned the clamps so that they will be more accessible in the future. Both of the tees were broken, one was completely disintegrated. Thanks again to this site for all the shared knowledge.
