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Fault codes - P2176 and P1516


Seasoned Member
Jan 12, 2022
My XLR/V(s)
2007 Black XLR-V
Anyone have any suggestions. I have a 2007 XLR V with 84k miles that I purchased about 5 months ago and have driven very little. A few days ago I went for a short drive and it ran fine, two hours later I started it and it would barely run. I had a few trouble lights on the dash and DIC said reduced power. I guessed it might be the MAF sensor because it had K and N air filters and I know if they have too much oil in them it could coat the MAF sensor and cause problems. So I disconnected the battery, cleaned the MAF and installed new stock filters. An hour later I started it up, took it for a ride and it ran great until the next time I tried to start it. I hooked up a code reader and had two faults, P2176 and P1516, cleared the faults and it ran fine again for a few starts, then the same problem. I can clear the faults and it runs good but the problem comes right back, but only on restart, once it's running it's fine until I shut it off. A little research told me it may have something to do with the actual throttle position not matching where the computer thinks it should be. So, do you think I'm looking at a dirty throttle body, a lose wire connection, a bad sensor or something else.
Any help would be greatly appreciated.
MosT manuals say not to clean the mass air flow or throttle body but there are countless videos on how to do it without damage. The throttle body is fairly cheap and easy to change so cleaning is worth a try. It needs to come off to clean. Then it most likely will need a idel learn reset which is done by a scan repair tool. So maybe line up someone who can do it before you try and clean. If it does not relearn on its on, it will be in limp mode while you go to the garage.
Problem solved, it turned out to be a loose connection on the wires that plug into what I believe to be the top of the throttle body. It is very hard to see and even harder to get your fingers on the connecter but once I discovered that it wasn't snapped in place I was able to work it on a little better. No more codes and the car is running great.
Yes it sure could have been a lot worse. I still need to get the connecter locked in place but at least I know what caused the problem.

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