Am I missing something?
 

I recently got my car back from the dealership after a transmission swap, and immediately noticed a loss of power. I plugged in the OBD2 scanner (that thing has paid for itself many times over by now) and pulled a P0174 bank 2 lean. Erased it and started her back up, still lacking power. No codes. Got home and scanned, P0171 bank 1 lean. Erased it. Went to go get gas, lacking power, get back check codes, P0131. Tonight i have been running diagnostics on the O2 sensor and it seems OK. I cannot find any air leaks in intake or exhaust. I am kinda lost here. Anyone know whats going on?

A little supplimental background on the issue. The engine builds slowly fine but if i mash on it, it boggs right down and sounds like it is throwing up/girgling mouthwash like an alien. I can get the RPMs up to 5k slowly but then it boggs down, i dont know if that is because i reached the "terminal" throttle position or if it just doesnt know what to do at that point. i am beginning to think that the dealer had the battery disconnected too long and didnt flash teh ECM. Other than that i have no idea. Would that cause this? will it self learn if i take it through a nice OBD cycle?

One other thing that crossed my mind is that perhaps they disconnected the fuel lines and reconnected them backwards causeing it not to build pressure(i have seen this at work before but things are a bit different with a common rail.) How can i check the pressure AFTER the pressure regulator and before the damper without the special service tool?

Take it back to the dealer if some more relearn miles doesn't help, but right now it appears to have a "lean" condition. Maybe an air leak. Is the idle OK? The battery disconnect time is irrelevant. ECM "flash" is not applicable. IF they had somehow crossed the supply and return fuel lines, it wouldn't run. Have the dealer check the fuel pressure if it eventually comes to that.

sounds like a maf problem

i will be taking it back to the dealer if i cant figure it out but i want to avoid that place like the plague, every time i go there it is something different that gets ****ed up. i was thinking MAF too but all the checks i can run show its OK. Plus i replaced it with the "updated" MAF 40k ago and there was NO previous signs of failure like last time and most peoples experience i have heard. I will keep diagnosing and let you guys know.

Keep em coming.

Just out of curiosity, did anyone ever try that electrical parts cleaner on the MAF? I remember someone metioning they were going to, but never saw an update.

It could still be the MAF. They could have physicaly broken it while removing it during the tranny swap. If that happened it might test out differently than one that went bad on it's own. That would also explain why it was so sudden.

what are the chances the dealer will admit that and cover it? I am gonna go get the MAF cleaner and give it a shot.

First take it to the dealer. If they just worked on it and now you have the problem they should admit it.

The Intake and MAF are removed during a tranny swap so it's very likely they messed it up. Especialy if it you noticed it right away. It's not like your window motor went out and you're blaming them for that. If you go screwing with it before bringing it in they'll blame it on you.

Just bring it in and explain the situation from the begining. It sounds like you did the right thing by waiting for a little while but you should do it as quickly as possible. The more time passes the less likely they will be to handle it.

BTW I work at a car dealer and can tell you they will admit mistakes a lot of the time. You just have to do it in a reasonable amount of time. A lot of people will come back a month later complaning about something. At that point it becomes difficult to know what really happened.

well i called the service manager directly as soon as i left the dealership. I had to get it home so i could do the wheel bearing/ball joint/LCA repair. He knows that it was a problem as soon as i left, i made sure of that. the funny thing i find is that when the service manager returned my call he said that he inspected teh car himself and drove it and didnt notice anything wrong. We will see.

P.S. i used the MAF cleaner today, nothing changed. although the thing looks new, all shiny and ****.