About a month ago I was driving and the idler puller fell off, which caused the belt to fall off. I then replaced the idler pulley and reattached the belt. A week later the service engine light came on and was giving a PO101 code (faulty MAF) and a PO171 (bank 1 - system too lean) and the car was idling very high, had lack of power, and would stall every now and then. I found out the MAF did need to be replaced and some of the vacuum lines as well. I thought by fixing those things the car would be fine, but now when the car is idling or I'm stopped, the RPMs will move up and down by themselves and sometimes it stalls. There is currently no error codes and the car does seem to run better when it's not too warm out. I'm hoping someone may have some advice because I have absolutely no idea what could be wrong!
Originally Posted by W-Body Store
