Hey guys I just made this video not sure what could be causing this. You can hear the idle is bouncing around and the wideband bounces with the exhaust. I checked the exhaust for leaks with seafoam and the only one I found was by the back tire where there is a clamp. Also I did a BLT at the throttle body and couldn't find any leaks. You guys have any ideas of what could cause this? If you watch the rpm's they don't move but it sounds like it has cams or something. Still need to finish the tune right now its just has a base tune. The guy who tuned it set it up for 42's instead of 60's so aces on here fixed that for me. Also you guys know what causes it to idle surge while its coasting? As soon as it comes to a stop the surging stops but the whole time your coasting it surges a couple hundred rpm's
2.8 pulley - 60's - magnaflow cat back - injen intake

Cobalt SS idle - YouTube

 

Did this start right after the tune? Check IAC and scan for any possible PENDING CELs

 

After the previous tune. Aces did a quick fix we still have to finish it I was just wondering if you guys had any ideas. I just picked up some tb cleaner so I'm going to try that.

 

I don't know then, any problems when you're driving other than coasting?

 

Mine does this slightly, but thats kinda expected being on E85. LOL. I wouldn't worry about it. Just needs some fine tuning.

 

I took off the tb and it's perfectly clean so that's not the problem. Maybe I can clean the map sensor.