I recently had a mechanic put in a new fuel pump. The fuel pump whistles pretty bad and my check engine light has come on (P0171 P0175) Bank 1, Bank 2. My truck is now stalling when it is hot (warmed up and I live in Vegas) and going downhill once warmed up from commute home. If I let it sit for a couple of minutes it will start back up. Do you think that the mechanic installed a bad fuel pump. I took it to another shop and they said the pressure is fine, but the fuel pump could lose pressure once it is warm? I am so lost and was wondering about the buzzing sound? PLEASE PLEASE give me some input

 

Blockage in the line perhaps? Old fuel filter? Sounds like fuel starvation or vapor lock.
You can still show good pressure and not have enough flow to satisfy the engine.

 

Did you take it back to the shop that did the work? Possibly a bad relay or sensor?

 

yeah, I have taken it back and have spent over $1,500 on additional procedures and it still dies. I have had them clean everything because they thought it was carbon build up. I have had my sensors replaced (MAF, ECR). I feel like they are ripping me off and I dont think that they know what they are doing. I am so frustrated and I feel like I am better getting advice on here than throwing money and hoping it will fix the problem. Please let me know what your opinions are on this matter.

 

Go back through your paperwork and check for the part number of the pump. Make sure the correct one was chosen.

And please make a sig so we know what year , engine, transmission, ect we are dealing with.