leaking FI, result in long crank to start. Last part of fuel pressure test is, leak down test.
2UZ-FE High Long Term Fuel Trims
- Thread starter Rednexus
- Start date
This site may earn a commission from merchant affiliate
links, including eBay, Amazon, Skimlinks, and others.
Thanks for the correction. I edited my post accordingly.
Got the autoline pro smoke machine yesterday and ran a test on the charcoal canister. totally backed up, so I've got a replacement on order from part souq. When I first unplugged the line between the CC and the fuel tank it took a few minutes to depressurise the tank. I'm amazed it can take that long. I hope the lines themselves aren't gunked up or they need to be replaced because that would be a big job. Maybe its reasonable with enough tank pressure that the flow is regulated though. It makes sense the flow would be regulated because the CC testing procedure is supposed to be done at .7 psi, so they would need to match that spec from the fuel tank. I think I'm correct about that.
I also plugged my exhaust with the smoke machine, and ran it for a few minutes to try and see if there were any leaks further up near the engine. I couldn't see anything. I could smell a tiny tiny bit, but I do have an extremely sensitive nose, and that could have been smoke coming from the tail pipe so hard to be sure. probably need to remove a fair bit more to see clearly. if this gets to the point where I replace the intake manifold gasket I'd do the test again with it being easier to see in the engine bay.
Next I'm going to plug this thing into the air intake. I figure I should plug the smoke line into the capped inlet on the top left of the intake manifold, and I'll remove the MAF so it doesn't get affect and block the air hose at that point too. Any thing else I need to be careful of?
I also plugged my exhaust with the smoke machine, and ran it for a few minutes to try and see if there were any leaks further up near the engine. I couldn't see anything. I could smell a tiny tiny bit, but I do have an extremely sensitive nose, and that could have been smoke coming from the tail pipe so hard to be sure. probably need to remove a fair bit more to see clearly. if this gets to the point where I replace the intake manifold gasket I'd do the test again with it being easier to see in the engine bay.
Next I'm going to plug this thing into the air intake. I figure I should plug the smoke line into the capped inlet on the top left of the intake manifold, and I'll remove the MAF so it doesn't get affect and block the air hose at that point too. Any thing else I need to be careful of?
Well I ran smoke in there and found nothing for the intake. Nothing in the exhaust test was visible for now. Next up, I need to do that fuel pressure test. waiting for a banjo bolt to arrive. Charcoal canister wont get here for a month so I need to move on under the assumption that it has contributed a bit, but its not the whole problem.
However! I did see fuel vapour residue in the region where the resonator connects to the air tube. I'm guessing by the design, that can contain this stuff in there, some of this residue expected. But I want to know, is it normal? and where does it actually come from? Is it coming back out of the main vaccum line somehow (backflow?) or is it coming from the small line connected to the fuel pressure regulator?
Check this video and let me know what you reckon...
However! I did see fuel vapour residue in the region where the resonator connects to the air tube. I'm guessing by the design, that can contain this stuff in there, some of this residue expected. But I want to know, is it normal? and where does it actually come from? Is it coming back out of the main vaccum line somehow (backflow?) or is it coming from the small line connected to the fuel pressure regulator?
Check this video and let me know what you reckon...
Check your fuel pressure, I have been through this before and every time it has been a fuel pump. I have a $15 chinese pump that I use to diagnose before buying an oem pump. Its cheaper and easier than checking fuel pressure if you dont already have the tools and rail adapter. The hardest part is removing the back seat.
Thanks @peacesells63 , I decided to invest in the OTC gauge to be better at diagnosis in general, and to be able to help out other people. Thats a cool trick with the cheap pump! I'm just waiting on the banjo bolt to get here and ill get into it. Although I suppose I could do a fuel flow test more easily in the mean time right now. Just not sure about the procedure for that.
@peacesells63 theres an interesting symptom for why I think it is going to be the fuel pump - after resetting fuel trims, the car never starts first crank. once started on the second crank, its got enough data to alter the STFT, and it starts. yes it could be a number of reasons, but it would make sense if it needs to do this to increase injector pulse to compensate for sub-optimal fuel delivery. I've realised I have everything I need to do fuel volume test, I just need the spec for the volume and duration I need. .95L per 30 seconds is what I get from chat GPT for a 2uz VVTI. any step by step instructions would be nice. I'm not sure if turning on the electronics in this car is going to automatically activate the fuel pump before I get a chance to activate the test in techstream.
Gunk is normal:
PCV hose DS, is connected to back side of throttle body, which hose coms from PCV valve, which threads into head cover.
PVC PS connect to resonator (air pipe), from PS head cover.
PCV (positive crankcase ventilation) is sucking crankcase vapors, which are oily.
When battery disconnected. It tales ECM an second to relearn. We almost always get, a delayed start, afterwards.
CC as I said earlier, needs replacing first. They cause a lot of engine running issue. On the 06-07 100 series. I also replace the CC pre filter.
Please, make sure to accurately weight both old and new CC, and post the CC P/N #.
Ill be sure to weigh both yes @2001LC . I just thought since I've never felt any vacuum on that vac line to the fuel pressure regulator at idle that maybe that gunk could affect it.
I think I found that connector, 5/16 fuel quick connect I believe. Looks the same as my picture.
www.efisolutions.com.au
They also sell the male end:
www.efisolutions.com.au
I believe this should match what my quick connector is in the photo.
I think I found that connector, 5/16 fuel quick connect I believe. Looks the same as my picture.
EFI Plastic Fuel Fitting Quick Connect Straight Female 5/16 ID Tube To Male 5/16 Barb 808-01
EFI Plastic Fuel Fitting Straight Female 5/16 ID Tube To Male 5/16 Barb - EFI Solutions
www.efisolutions.com.au
They also sell the male end:
EFI Plastic Fuel Fitting Quick Connect Straight Male 5/16 Tube To Male 5/16 Barb 817-01
EFI Plastic Fuel Fitting Straight Male 5/16 Tube To Male 5/16 Barb - EFI Solutions
www.efisolutions.com.au
I believe this should match what my quick connector is in the photo.
Last edited:
These fuel pumps have a resistor circuit that varies the pump speed, so they do some weird stuff when the pump gets weak. My wifes 100 had a cold stumbling issue for several years. It started getting worse, but only in the colder weather. Eventually the CEL came on when the LTFT's got bad enough. After digging into it and watching the STFT's, LTFT's, injector duty cycle and O2 sensor outputs, it had to be a fuel supply issue with correlation to pump speed. Under wide open throttle when the pump is running at 100%, eveything was normal - but cruising on the highway with little load (when the resistor curcuit is in play) the LTFT's were in the mid 20% to mid 30% range. Higher on bank 2, since that is further from the supply. As soon as I would floor it, the LTFT's were perfect again.
Very similar to my situation! I've also suspected bank 2 being further away would be worse if its fuel pump due to proximity, bank 1 gets fuel first if pressure is not maintained. bank 2 also has better compression than bank 1 in my case so I dont see how it would be compression.
When I floor it, fuel trims go to +4.7 on both banks. I don't know if this is just what we call a "sentinel value" or dummy data in programming though and open loop (I forget if its open loop) I have also noticed at certain levels of throttle the fuel trims can become equal again, but still high, so thats very interesting if the pump does have certain states where its providing enough pressure to satisfy both banks (but still compensating)
Explain to me how from injector duty cycle and the other data you were able to determine it was the fuel pump in your case?
That resistor circuit you describe explains a lot, like why LC2001 says fuel flow test is important, not just pressure. I'm itching to get this done. what fuel flow rate am I looking for?
When I floor it, fuel trims go to +4.7 on both banks. I don't know if this is just what we call a "sentinel value" or dummy data in programming though and open loop (I forget if its open loop) I have also noticed at certain levels of throttle the fuel trims can become equal again, but still high, so thats very interesting if the pump does have certain states where its providing enough pressure to satisfy both banks (but still compensating)
Explain to me how from injector duty cycle and the other data you were able to determine it was the fuel pump in your case?
That resistor circuit you describe explains a lot, like why LC2001 says fuel flow test is important, not just pressure. I'm itching to get this done. what fuel flow rate am I looking for?
I decided to try and run a fuel flow test this way, no regulator in the loop, not sure if its acceptable to do something like this, it was the only way to hook it up with what I had. Let me know if it's a bad idea.
Got this far and techstream open on the mac, slow as, but each time I try to run the active fuel flow test it crashes, so everything is packed up again while I figure out how to activate the fuel pump. Any pointers on how to manually activate the relay safely, without shorting a connection to the ECM would be helpful if it can be done.
Got this far and techstream open on the mac, slow as, but each time I try to run the active fuel flow test it crashes, so everything is packed up again while I figure out how to activate the fuel pump. Any pointers on how to manually activate the relay safely, without shorting a connection to the ECM would be helpful if it can be done.
Yeah its looking like tech stream might not be able to do a fuel flow test with my version and my mini vci which crashes. I also tried to activate the relay manually but I think its only one part of the chain and wont stay enabled for more that a few seconds. on ig (not engine running though).
I'm sure I'll be ok to do a fuel pressure test, but wondering how you guys activvate the pump manually to do a fuel flow test on a vvti @2001LC ?
maybe your mx+ tool can do active tests or something?
I'm sure I'll be ok to do a fuel pressure test, but wondering how you guys activvate the pump manually to do a fuel flow test on a vvti @2001LC ?
maybe your mx+ tool can do active tests or something?
I use Tech Stream (TS). I run TS Mini VCI, in Oracle virtualbox, running on windows XP. I do not log online to Toyota.
Sometimes TS can be pain, to get up and running. A whole thread develop around it, in ih8mud. But once working usually is okay.
I had to give up on techstream, kept on crashing when I did the active test for some reason. But the good news is I got my fuel pressure test and it came back between 28-31psi which I'm pretty sure we know is a fail - FSM states 38 to 44 psi.
I've got a video here, just jump ahead to 1m30s.
I also noticed when snapping the throttle pressure boosted but seemed limited to about 45psi so that would suggest to me the regulator is working, what do you guys think?
Should I verify regulator is ok next? And then next replace fuel filter before buying a pump?
Doesn't look like part souq have fuel pumps for my model anymore. Perhaps I should start by running some BG44k system cleaner while I'm waiting for one.
These 5/16th fuel quick connect and barb worked perfectly from EFI solutions in Brisbane.
I've got a video here, just jump ahead to 1m30s.
I also noticed when snapping the throttle pressure boosted but seemed limited to about 45psi so that would suggest to me the regulator is working, what do you guys think?
Should I verify regulator is ok next? And then next replace fuel filter before buying a pump?
Doesn't look like part souq have fuel pumps for my model anymore. Perhaps I should start by running some BG44k system cleaner while I'm waiting for one.
These 5/16th fuel quick connect and barb worked perfectly from EFI solutions in Brisbane.
Last edited:
As I recall you did replace the CC?
I would R&R fuel filter now. Then backflush old fuel filter, to see what come out.
98% chance you'll still need a new fuel pump, rubber cushion and fuel tank gasket (between fuel pump assy & gas fuel tank).
2% chance, something other than fuel pump.
The Resistor Assembly Fuel - Toyota (23080-50170) 06-07, delivers current to the fuel pump, based on engine RPM. Fuel pump is multi speed, pumping faster at higher engine RPM. IIRC. The FSM has a test to check it's working to spec. 2% chance electrical circuit issue. Todate, all I've had low fuel pressure, was bad fuel pump.
Pumps manufacturer, changed in 2022 to Aisan Industry Co., Ltd.
I don't which fuel pump or know how your 200 series fuel tank(s) are set up.
This P/N for the 100 series VVTi 2006-07. If partsouq show your's the same P/N. Then fuel pump is available.
23220-50160 fuel pump 06-07 100 series (partsouq does show in stock)
23249-50061 rubber cushion (bottom fuel pump)
77169-33020 gasket fuel tank.
Alternant fuel pump:
Denso 950-0210 (fit 06-07) is not series 100. List for other 4.7L Sock not included.
Denso stop making fuel pumps. But, we still find some old inventory around. But "some" may be bootleg junk.
Toyota & lexus Dealership have the new fuel pumps. Some even have old inventory!
I would R&R fuel filter now. Then backflush old fuel filter, to see what come out.
98% chance you'll still need a new fuel pump, rubber cushion and fuel tank gasket (between fuel pump assy & gas fuel tank).
2% chance, something other than fuel pump.
The Resistor Assembly Fuel - Toyota (23080-50170) 06-07, delivers current to the fuel pump, based on engine RPM. Fuel pump is multi speed, pumping faster at higher engine RPM. IIRC. The FSM has a test to check it's working to spec. 2% chance electrical circuit issue. Todate, all I've had low fuel pressure, was bad fuel pump.
Pumps manufacturer, changed in 2022 to Aisan Industry Co., Ltd.
I don't which fuel pump or know how your 200 series fuel tank(s) are set up.
This P/N for the 100 series VVTi 2006-07. If partsouq show your's the same P/N. Then fuel pump is available.
23220-50160 fuel pump 06-07 100 series (partsouq does show in stock)
23249-50061 rubber cushion (bottom fuel pump)
77169-33020 gasket fuel tank.
Alternant fuel pump:
Denso 950-0210 (fit 06-07) is not series 100. List for other 4.7L Sock not included.
Denso stop making fuel pumps. But, we still find some old inventory around. But "some" may be bootleg junk.
Toyota & lexus Dealership have the new fuel pumps. Some even have old inventory!
Last edited:
Two test you did not show in video:
Fuel pump pressure test, engine off, run fuel pump through TS. Test fuel pressure regulator.
Last test is leak down. Which is after engine running test (fail).
Fuel pump pressure test, engine off, run fuel pump through TS. Test fuel pressure regulator.
Last test is leak down. Which is after engine running test (fail).
Charcoal canister arrives in the next few days, along with a new fuel filter.
For the tests - unfortunately I can't get techstream to behave on my mac m2, just crashes with active fuel test. And on my AMD laptop the vm wont even boot so must be an architecture thing. Perhaps I could emulate similar test it by turning the IG on and off a few times, but with engine off (since fuel pump runs for a few seconds I'm told).
Leakdown tests didn't show much change, here's a vid of that. it didn't budge from 28 psi over 5mins, so I guess the check valves are all good there.
Partsouq is a little hard to decipher on this one with regard to substitutions.
The full assemblies show up as compatible with my model (UZJ200R-GNAEKQ)
Part 7702060390 or: 7702060391
...But neither are in stock. The sub components are in stock if ordered individually, just not sure if that would really get absolutely everything though if not ordering the full assembly.
If I google search "partsouq 7702060391", it suggests 7702060392 as a substitute, but clicking on that part doesn't explicitly say its compatible with my model 07/08, it says 2012 onwards.
For the tests - unfortunately I can't get techstream to behave on my mac m2, just crashes with active fuel test. And on my AMD laptop the vm wont even boot so must be an architecture thing. Perhaps I could emulate similar test it by turning the IG on and off a few times, but with engine off (since fuel pump runs for a few seconds I'm told).
Leakdown tests didn't show much change, here's a vid of that. it didn't budge from 28 psi over 5mins, so I guess the check valves are all good there.
Partsouq is a little hard to decipher on this one with regard to substitutions.
The full assemblies show up as compatible with my model (UZJ200R-GNAEKQ)
Part 7702060390 or: 7702060391
...But neither are in stock. The sub components are in stock if ordered individually, just not sure if that would really get absolutely everything though if not ordering the full assembly.
If I google search "partsouq 7702060391", it suggests 7702060392 as a substitute, but clicking on that part doesn't explicitly say its compatible with my model 07/08, it says 2012 onwards.
Best abd easiest: If you've a VIN # or frame #, us it to find your vehicle in PQ.
Toyota sub P/N, are the new P/N. You can cross check with toyota parts web portal or parts counter.
That is the whole assemble. You can just buy pump. We also buy a rubber grommet sit on bottom (you may not have)
Toyota sub P/N, are the new P/N. You can cross check with toyota parts web portal or parts counter.
That is the whole assemble. You can just buy pump. We also buy a rubber grommet sit on bottom (you may not have)