Car Idles at 4000rpm Please help
 

Short version. Car is on MS2 with VVTuner it ran fine up until I went back to stock for my inspection. I've been stock for the past 2 months. Last night I put the turbo and MS back in. Fired up and idled at like 1500, which is normal. This morning I took it for a quick drive. It's pig rich basically constantly and as soon as I hit boost it started to idle high ~2500rpm. The car has done this before but usually I just stomp on it and it idles normal again. I tried this method and it just got worse.

Now I start it and it immediately jumps to 4000rpm and stays there or goes up more. I'm getting rather flustered. Plugging the stock ecu back in it starts up fine and idles fine, well fine for bigger injectors and vvtuner but not 4000rpm. I've attached a datalog but I'm not sure it'll be any help.

Any help would be greatly appreciated as this is really annoying, the car isn't really drivable.

Sounds like a vacuum leak, I'd check there first. It's most likely idling "fine" on the stock ECU because it's running big rich and unable to even get to 4000rpms.

you either have a major vacuum leak or a completely fubared tune.

ECU serial #?

I think its my retarded cold start settings. I had to mess with them a lot to even get it to start somewhat acceptable (2-3 times turning the key) in the cold. I was pissed so I went an beat on the car with a friend watching the afr's so we were safe in boost. As it heated up the idle dropped and the afr's leaned out.

Also it seems to actually be pulling better vacuuming now. It used to pull 22inHg then went to 20inHg then I went to stock and it stayed around 20inHg, now its back to 22...So I don't know I'll post my cold start settings or email Rev about help

Be aware that the walbro 255 will not play nicely with the OEM NB Fuel Regulator at Idle and low power. Its written in a few threads here and in some of the vendor's websites.