06-07 Fuel pumps are different in size than the earlier version, so make sure you get the right one. The clerks at Advance aren't always the brightest of the bunch.
Sudden Loss of Power AGAIN - On road with family [St. Louis,MO]
- Thread starter frogers935
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- Thread starter
- #22
Thanks everyone.
Yep advance only had 1 in stock and does not fit. I have decided to spend another day in St Louis. Tomorrow I will see if any dealerships have the pump, may take it in a mechanic that was recommended but the fuel pump makes sense. Can't risk being disabled on the highway with family.
Yep advance only had 1 in stock and does not fit. I have decided to spend another day in St Louis. Tomorrow I will see if any dealerships have the pump, may take it in a mechanic that was recommended but the fuel pump makes sense. Can't risk being disabled on the highway with family.
- Thread starter
- #24
@vj95 what were you symptoms?
The '06 has an integrated throttle control module with sensor and motor in a single unit very much like the HVAC mix valves. Wiring diagram attached for reference. The picture below shows the unit with single connector for motor and sensor.
OP: If this was my vehicle, I would look at the Techstream data a bit more before committing to a fuel pump. Are fuel trims positive on both banks? Is your throttle body clean and moving freely? etc. The symptoms you are describing could also be caused by a throttle body problem, crank sensor problem (when hot) etc, etc.
- Thread starter
- #27
Thanks @white_lx thats why I couldn't find a P/N.
Throttle body is clean. I don't see anything to diagnosis crank position sensor in the manual, is there a resistance to check?
Working on techstream. Had it working on virtual box but it is painfully slow, trying to get it installed on 64 bit.
Throttle body is clean. I don't see anything to diagnosis crank position sensor in the manual, is there a resistance to check?
Working on techstream. Had it working on virtual box but it is painfully slow, trying to get it installed on 64 bit.
- Thread starter
- #28
Also the suggestion to make sure I don't run under a half of tank made me think about both situations of the stall.
Both happened when I was near empty. Both when I was stopped and tried to move again. Both had the same pending code of P0174
Both happened when I was near empty. Both when I was stopped and tried to move again. Both had the same pending code of P0174
Second this. Ask for brad.
My bet is on the fuel pump, good luck man hope that fixes it and you guys get on your way, safe travels.
OP: Any update?
- Thread starter
- #32
Update: I was able to go to MT Schiele yesterday morning, thanks to all for suggesting them and @SammyT96LX450 for giving them a heads up that I was coming. Both Aaron and brad were great and I would highly recommend them to anyone.
Aaron measured the fuel trims and bank#2 was showing problems. Ended up replacing both O2 sensors and the readings went back to normal. There was some question as to whether it was the throttle body but when he removed the O2 sensor on bank#2 it looked bad (some weird coloring).
I made it to Manhattan, KS without issue and am on my way to CO with a 7hr leg to drive today, hopefully all goes well.
I was thinking of getting a throttle body just in case ($$$) but in my search for issues with it on mud I came across this THREAD which refers to the same thing I was seeing with the RPM fluctuating at 2k (~65mph). On my last leg I did not notice any fluctuations. It makes sense to me that it is/was a sensor as Aaron measured and as described by @white_lx but what caused it to go bad?? Is it possible the pump is going too? If it was only a bad fuel pump then resetting it via disconnecting the battery would not get it running again with a only a 5min cool down???
So I have had the MAF and O2 sensor fail and I am at 126k miles. I don't think these are common issues on our trucks so I am searching for a root cause. Seeing that I am about 1k miles from home, throwing $$$/parts in it sucks but may be necessary.
Opinion?
Maybe have Lexus in CO check throttle body?
Order a fuel pump?
Just replace throttle body?
As a side note I am sick of my Mud terrains, it makes it hard to tell if my engine is not happy or is it just the noisy/rough ride. If anyone in CO wants a cheap set of Cooper STT let me know I may have to get some ATs.
This is turning into a very $$$ trip....
Aaron measured the fuel trims and bank#2 was showing problems. Ended up replacing both O2 sensors and the readings went back to normal. There was some question as to whether it was the throttle body but when he removed the O2 sensor on bank#2 it looked bad (some weird coloring).
I made it to Manhattan, KS without issue and am on my way to CO with a 7hr leg to drive today, hopefully all goes well.
I was thinking of getting a throttle body just in case ($$$) but in my search for issues with it on mud I came across this THREAD which refers to the same thing I was seeing with the RPM fluctuating at 2k (~65mph). On my last leg I did not notice any fluctuations. It makes sense to me that it is/was a sensor as Aaron measured and as described by @white_lx but what caused it to go bad?? Is it possible the pump is going too? If it was only a bad fuel pump then resetting it via disconnecting the battery would not get it running again with a only a 5min cool down???
So I have had the MAF and O2 sensor fail and I am at 126k miles. I don't think these are common issues on our trucks so I am searching for a root cause. Seeing that I am about 1k miles from home, throwing $$$/parts in it sucks but may be necessary.
Opinion?
Maybe have Lexus in CO check throttle body?
Order a fuel pump?
Just replace throttle body?
As a side note I am sick of my Mud terrains, it makes it hard to tell if my engine is not happy or is it just the noisy/rough ride. If anyone in CO wants a cheap set of Cooper STT let me know I may have to get some ATs.
This is turning into a very $$$ trip....
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I am glad you found MT Schiele - best guys in St. Louis for us.
I hope you don’t have any more issues
What are the details on your Coopers?
I hope you don’t have any more issues
What are the details on your Coopers?
I had similar issues with our 06. Mine would cut out just driving down the freeway at 65-70. Would regain quickly but still annoying and scary. But also pulling onto any street to take off would not go, completely randomly. No codes, no sign of any issues. My fuel pump went out (another story I can relate too died 40 miles West of Albuquerque, confusion by Lexus dealership of what pump was correct) and replaced so that was new long before any of these symptoms started. Ended up replacing the throttle body. No issues after that.
Really sounds more sensor related to me.
If I were going to spend money on a hard to diagnose problem....I put it toward the throttle body.
If I were going to spend money on a hard to diagnose problem....I put it toward the throttle body.
Thanks for the update. Glad to read you are back on the road.
I'm wondering if there was a wrong diagnosis when you had the same symptoms earlier and they replaced the MAF. Did that solve the problem at the time?
The first sensor after the exhaust manifold is a wideband air-fuel sensor on '06 and '07 models. Those look like oxygen sensor, but are different. They are more prone to failure than oxygen sensors. They run at much higher temperatures than O2 sensors and that may explain why they are more prone to failure, maybe? Because these have a shorter life than oxygen sensors and if the problem was solved by replacing it, I would not worry about stocking other parts too much.
Attached is a very interesting article about A/F sensors and how to diagnose them. The article mentions Toyota A/F sensors have a typical life of 80,000-110,000 miles (page 8), so you seem to be doing good at 126k miles. If anything, you may want to keep an eye on the other A/F sensor.
I'm wondering if there was a wrong diagnosis when you had the same symptoms earlier and they replaced the MAF. Did that solve the problem at the time?
The first sensor after the exhaust manifold is a wideband air-fuel sensor on '06 and '07 models. Those look like oxygen sensor, but are different. They are more prone to failure than oxygen sensors. They run at much higher temperatures than O2 sensors and that may explain why they are more prone to failure, maybe? Because these have a shorter life than oxygen sensors and if the problem was solved by replacing it, I would not worry about stocking other parts too much.
Attached is a very interesting article about A/F sensors and how to diagnose them. The article mentions Toyota A/F sensors have a typical life of 80,000-110,000 miles (page 8), so you seem to be doing good at 126k miles. If anything, you may want to keep an eye on the other A/F sensor.
edit: nvm read your update! glad you are back up. my alt died on a road trip that tripped other electrical gremlims down the road. so yeah roadtrip headaches suck
Lexus Service Center Denver | Aurora Lexus Repair & Dealership "Kuni Lexus" is just off south I-25 and Believe. I can't recommend a name there, as my guy retired. But they've a good shop.
Toyota Dealership Denver CO | Near Aurora & Highlands Ranch "Groove Toyota" Is about 10 minutes off HWY from same point. They would be cheaper and has some good guys. Travis is a 20 year master diagnostician, and is who I'd ask for.
You can PM me for contact info and bring by (in same area) and I'll look at for you. But unless it acts up, they nor I will have anything to go on. So you may waste your time. BTW, I do have a few used Throttle body on the shelve from 07-08 2UZ-fe VVTi like yours. But even new OEM, aren't too expensive in the VVT. Not near the cost of older ones.
While you ascend & descend passes in Colorado Rocky Mountains. If power is lost again. I then look to fuel pump. It may be part of what has effected the A/F (front O2) sensors. If fuel mixture leans out. Then cylinder heads run hotter and so do the A/F sensors. We don't know why they (fuel pumps) test good while this happens. But replacing them has corrected the high altitude stall issues we've seen here.
I'm going to be replacing one myself in and 07LX I just bought, when I get time. I had stall issues as I crested the summits and began my descent. What I'm thinking happened is, as I let off gas peddle after climbing. The fuel pump drops back to low speed through relay. On my first stall I saw lean condition code both banks. Now just driving around Denver, I have both CAT codes. Yet one CAT and other stuff was just replaced by PO. Three or four different shop worked on it, than PO gave up sold.
So my plans is too start downstream and work through. That means gas cap first. Than fuel pump. My test will included driving over passes with each change/repair I make.
Toyota Dealership Denver CO | Near Aurora & Highlands Ranch "Groove Toyota" Is about 10 minutes off HWY from same point. They would be cheaper and has some good guys. Travis is a 20 year master diagnostician, and is who I'd ask for.
You can PM me for contact info and bring by (in same area) and I'll look at for you. But unless it acts up, they nor I will have anything to go on. So you may waste your time. BTW, I do have a few used Throttle body on the shelve from 07-08 2UZ-fe VVTi like yours. But even new OEM, aren't too expensive in the VVT. Not near the cost of older ones.
While you ascend & descend passes in Colorado Rocky Mountains. If power is lost again. I then look to fuel pump. It may be part of what has effected the A/F (front O2) sensors. If fuel mixture leans out. Then cylinder heads run hotter and so do the A/F sensors. We don't know why they (fuel pumps) test good while this happens. But replacing them has corrected the high altitude stall issues we've seen here.
I'm going to be replacing one myself in and 07LX I just bought, when I get time. I had stall issues as I crested the summits and began my descent. What I'm thinking happened is, as I let off gas peddle after climbing. The fuel pump drops back to low speed through relay. On my first stall I saw lean condition code both banks. Now just driving around Denver, I have both CAT codes. Yet one CAT and other stuff was just replaced by PO. Three or four different shop worked on it, than PO gave up sold.
So my plans is too start downstream and work through. That means gas cap first. Than fuel pump. My test will included driving over passes with each change/repair I make.
BTW: A/F and O2's are designed to take heat. But replacing both A/F has been reported in mud, to had very good results in the VVT with CAT DTC, that keep returning even after CAT replaced.
Excessive heat possibly.
Funny color many mean coolant. Coolant will damage CAT and sensors.
What did yours look like?
Excessive heat possibly.
Funny color many mean coolant. Coolant will damage CAT and sensors.
What did yours look like?
This sounds very familiar to what I just had happen to me in the middle of no where this weekend. It sounds like the fuel pump. My LC 2007 has been acting weird especially when hot. Like when accelerating its like im actually taking my foot off the gas every other second. Drove from Dallas to Amarillo and it died giving me P0171 and P0174 codes. Everyone said MAF. So i replaced it and made it 60 miles. Temps were 106 and when i slowed down at a small town i lost power and no codes. Had it towed back to Amarillo and they tested fuel line pressure and it was 30 psi. The truck would restart and run once cooled down.
Here's the thing, its easy to replace on the side of the road IF you find the right pump. I had a spare and turns out they sold me the wrong one. I was about to do a write up about it.
Here's the thing, its easy to replace on the side of the road IF you find the right pump. I had a spare and turns out they sold me the wrong one. I was about to do a write up about it.