Irregular Idle/Startup/WOT issues
Irregular Idle/Startup/WOT issues
Hey everyone,
About 3 months ago, I got my car retuned (due to new turbo being installed). Drove it around for about a week and had no issues at all, it ran amazing. I then parked the car for about a month and half (since I had to go to school) and when I came back, the car was acting extremely different. Not sure if its the tune acting up or something happened to the car when it was sitting.
Driving on the highway and cruising around town, the car runs fine. However, on idle, startup, and WOT is where its having some issues. When coming to a stop (like at a stop sign or red light) the AFRs will bounce all over the place. The AFR will either dip down very rich (~10.5-13) or become extremely lean (~16-18+). Sometimes it will try to stall, sometimes it will remain at a constant idle. If I let the car sit long enough, it will eventually balance out after 10-20 seconds (bringing the AFR back to ~14.7). Cold starts for the most part are fine, (sometimes will run a bit lean, but if i tap the gas, it will level out). However, with warm starts, the car will either start up fine, or it will run very rich and refuse to start (I've oddly only had this issue when re-filling the car with gas). It will sputter and die out unless I hold the gas pedal to the floor, and rev it a bit. On WOT, the car tends to run very rich during spool-up. The AFR drops to ~less than 10-10.5 and work its way back up to ~11.1 by redline - I am now getting about 3-6 counts of knock on most pulls, when before it sat, it had pretty much no knock on pulls. (The car has also been overboosting recently)
On a side note, after driving it for a few days upon my return from school, I got a CEL - P0171 (system running lean) - Looked around forums and people recommended cleaning the MAF sensor and looking for vacuum leaks - There were no leaks that I could find and I cleaned the MAF sensor which got rid of the CEL, but the car is still having issues.
I'm completely stumped on this issue - Any help is appreciated!
About 3 months ago, I got my car retuned (due to new turbo being installed). Drove it around for about a week and had no issues at all, it ran amazing. I then parked the car for about a month and half (since I had to go to school) and when I came back, the car was acting extremely different. Not sure if its the tune acting up or something happened to the car when it was sitting.
Driving on the highway and cruising around town, the car runs fine. However, on idle, startup, and WOT is where its having some issues. When coming to a stop (like at a stop sign or red light) the AFRs will bounce all over the place. The AFR will either dip down very rich (~10.5-13) or become extremely lean (~16-18+). Sometimes it will try to stall, sometimes it will remain at a constant idle. If I let the car sit long enough, it will eventually balance out after 10-20 seconds (bringing the AFR back to ~14.7). Cold starts for the most part are fine, (sometimes will run a bit lean, but if i tap the gas, it will level out). However, with warm starts, the car will either start up fine, or it will run very rich and refuse to start (I've oddly only had this issue when re-filling the car with gas). It will sputter and die out unless I hold the gas pedal to the floor, and rev it a bit. On WOT, the car tends to run very rich during spool-up. The AFR drops to ~less than 10-10.5 and work its way back up to ~11.1 by redline - I am now getting about 3-6 counts of knock on most pulls, when before it sat, it had pretty much no knock on pulls. (The car has also been overboosting recently)
On a side note, after driving it for a few days upon my return from school, I got a CEL - P0171 (system running lean) - Looked around forums and people recommended cleaning the MAF sensor and looking for vacuum leaks - There were no leaks that I could find and I cleaned the MAF sensor which got rid of the CEL, but the car is still having issues.
I'm completely stumped on this issue - Any help is appreciated!
Last edited by 4G63_Crazy; Mar 20, 2020 at 06:15 PM.
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