Here's the story on my truck.


Spits and sputters between 40-60 during heavy acceleration and on rare occasions will jerk/pop while at a steady speed. No engine or wrench lights.

I thought it might be the fuel filter and changed that, it didn't help. I also ran two bottles (on 2 separate occasions) of Duralube extreme fuel system cleaner, that didn't help either. So, I took it to the Ford dealer for a diagnostic. They had a hard time getting it to act up but said it finally misfired on #8 and recommended replacing the ignition coil and plug. I did that, still have the same symptoms. So, I thought it might be the fuel injector and changed that. Still same symptoms and ZERO dummy lights.

After several YouTube videos, I thought it might be the TPS and got one. Before I changed that however, I cleaned the Mass Air Flow sensor, still same symptoms. I finally changed the TPS, but the engine wouldn't start or run at all, no warning lights yet. When I put the old TPS on, it would run. I unplugged the TPS and it still ran but very rough. Now the engine light IS on! Thinking I purchased a bad part, I took it back to O'Reilly's and they warrantied it out and gave me a new one. I had 19 PO codes. I changed the TPS again, and, it won't start or run at all. Put the old one on and it runs. They cleared the codes and told me they think it could be the ECM/PCM.

Why will a new TPS not work? Any ideas here? I can use any help you can give. I still have the same issue of hesitation @ 40-60 during hard acceleration. No hesitation during a moderate acceleration.


Looking forward to hearing from you.


Thanks!


Richard L. Ballew

 

Your signature would help if it said 05 supercrew 5.4 3v and xxx miles . Plus where you live makes a difference Texas versus alaska etc .
So anyway is it making any noise , when was your last tune up plugs /boots etc .
I can tell you that I lost my throttle body around 70k or so, seems they had a series of bad ones I think the defective number started with 3 instead of the newer 8 . You can take it off and clean it with throttle body cleaner .
The TPS tells the computer where the throttle plate is at, it has sent a series of pulse commands to the motor module on the other side if it doesn't match it shuts it down . The pcm watches the signal from the foot pedal and all must be in sync .
My guess is your codes should show something about that . I had cleaned my throttle body and changed my TPS and it would still shutdown suddenly in so many days . . So I put the updated one in and that was years ago no more problems there. I think the decoder on the motor module was flaky .
I would contact clean that TPS plug and motor plug . . Just maybe that bad tps you have causes the pcm to ignore it and it is putting in a default value, a new one is really confusing it and it won't start . Got me confused . Got my new upgraded throttle body on ebay for around $200.