Acceleration problem 2001 tundra

[rush1571]

Thanks! mitchr. I didn't know they would do that. I took it and there were no codes - it said "PASS". They suggested some "B-12" fuel system cleaner so I bought some and will put it in the next time I fill up - it can't hurt, right?

[mitchr]

Originally Posted by rush1571

Thanks! mitchr. I didn't know they would do that. I took it and there were no codes - it said "PASS". They suggested some "B-12" fuel system cleaner so I bought some and will put it in the next time I fill up - it can't hurt, right?

No, it can't hurt. The dealer's usually push BG fuel additives. If you get the total system cleaner it is pretty expensive, around $20-$40. It really is baffling what you have since I can't remember anyone else with those symptoms.

[dwagner825]

I was wondering how much you have driven the truck since the O2 sensors were replaced. My thinking is maybe the truck's computer is relearning the fuel/air ratio's for the new O2 sensors. Since the old ones were bad the computer had probably stored bad mixture combinations at different throttle levels. Did you or they reset the computer by disconnecting the battery?

Dan

[rush1571]

Thanks for the input on the BG additive. I just got a bottle/can of stuff you put in the tank. I did call the dealer and ask them what the fuel injection & TB service consisted of - they told me the hook the fuel system up to a machine and remove the TB for cleaning. So from what I've read on other posts this is the best/right way to have it done.

I haven't disconnected the battery and I don't know if the dealer did or not. I'm gonna try that tonight. I'll keep you posted!

I really appreciate the suggestions that you guys are giving. I hope I can return the favor in the future.

Oh by the way, I've driven it a little less than 1,000 miles - over 2 tanks since all this started.

[rush1571]

I tried disconnecting the battery for 30 mins but it didn't help. I was searching and found a thread below. I have a K&N drop-in filter. I'm going to try putting a regular air filter in and see what happens.

I installed the K&N about 10,000 miles ago. The scenario that I'm thinking about here is that when they did the FI service and TB cleaning that there may be a need for more air and it can't get it with the K&N. (This seems to not make any sense though since the K&N is a high flow filter. Maybe it's getting too much air??)


losing power under hard accel.

[rush1571]

Ok...I took the K&N filter off and put a stock one in, changed the PCV and chagned the oil. Seems to only occur in 2000-2500 rpm range - almost like it misses on and off until it's past 2500rpm.

Would the computer cause this or would this more likely be a mechanical problem? The only other things I can think of is fuel pressure regulator ($100+) or fuel pump (I don't even want to think about that one!)

Trey

[mitchr]

Originally Posted by rush1571

Ok...I took the K&N filter off and put a stock one in, changed the PCV and chagned the oil. Seems to only occur in 2000-2500 rpm range - almost like it misses on and off until it's past 2500rpm.

Would the computer cause this or would this more likely be a mechanical problem? The only other things I can think of is fuel pressure regulator ($100+) or fuel pump (I don't even want to think about that one!)

Trey

What about the fuel filter? I get my threads mixed up but I was reading one today about that causing performance problems with several members trucks. You have done everything else so what do you have to loose? I think it is located under the truck on the drivers side.

Mitch

[rush1571]

Originally Posted by mitchr

What about the fuel filter? I get my threads mixed up but I was reading one today about that causing performance problems with several members trucks. You have done everything else so what do you have to loose? I think it is located under the truck on the drivers side.

Mitch

Yep, did that already.

[mitchr]

PCV valve? Or whatever it is called in our trucks.

[rush1571]

Yep, that too...(PCV valve). I give up! I'm going to take it back to the dealer and make them ride in it again. Hopefully, I can duplicate the symptoms. So far, it has done it every time I have tried to duplicate the symptoms. Last time I took it to them, the service manager rode with me (and drove it too) and told me he thought everything was normal. I have had several people from work ride with me and they recognize it immediately when it does it.

Wish me luck! I'll keep you posted...

[4.7 vvt-i]

Maybe a long shot but if your TPS (throttle position sensor) is shot it will cause lurching/hesitation. Had that on my EFI F150 once.

[rush1571]

Well guys, I brought it in to the dealer yesterday. They rode with me and acknowledged the symptoms that I was experiencing. I felt like the problem was half solved just with the satisfaction that they didn't think I was FOS!!

After several test rides with the service manager and 2 technicians, they gave me a loaner and said to leave it with them so they could play with it.

They called today and told me they've ordered a new transmission for it. Seems there were brass filings (dust) in the pan when they opened it up. This is wild because 2 weeks ago they did a full transmission service and I witnessed the fluid drain as well as looked at the pan - looked clean to me as well as the tech that was doing the work (and he was not a young kid either!).

Oh BTW, it's under warranty with 49,400 miles. I just hope that solves the problem. Whether it does or not, I feel a little comfort in knowing that we caught a major problem before it got too bad.

I'll give another update when I get it back on Monday. Until then, I will be less of a man riding around in a POS Corolla loaner!!!

[rushje]

I promised an update - a little late but better than never.
After the new transmission, I was still having the problem. I went back to the dealer and made the service manager ride with me. (this is the one that conned me into a transmission fluid service on the second trip in for this problem). He got the OBD and plugged it in and we went for a ride. Again, nothing showed up one the OBD yet he acknowledged the symptoms. And oh, BTW he admitted that they were guessing when they replaced the transmission and that there was nothing wrong with it. He told me the hesitation was normal and that I should get used to it and that I was oversensitive to the "Fly by wire technology". What a jackdonkey.

Well I took it to an independent shop and for 65 bucks they told me to replace the fuel pressure regulator. That did the trick!! We hooked up a pressure gauge to the fuel line, duct taped it to the windshield and went for a ride. The needle on the gauge fluctuated from 25 to 60 psig and matched the hesitation that I was feeling. (spec pressure is ~40 psig steady). So I ordered a regulator from the OTHER local Toyota dealer, installed it in all of 3 minutes and she runs like a spotted ape now!! The mechanic at the ind. shop told me it was likely that the dealer damaged the regulator during the fuel injection service by dead-heading the pump downstream of the regulator on the return line in order to keep the cleaning chemicals from going back to the tank. This is not the correct way to perform a fuel injection service according to him.

I've contacted Toyota corporate and have a complaint against the dealer but haven't spoken to anyone at corporate yet. The dealer was supposed to contact me by last Thursday but did not. Any suggestions as to how to get the dealer to pay me back for my troubles (at least the $65 diagnostic fee and the $120 for the fuel pressure regulator)?????

[KLS]

If you have some paper documentation you could try small claims court.


Ken