Ok so car was flawless up until about a month and a half ago. Was on the 2.9 inch pulley (TVS) and 60lb injectors. Only code that was ever coming up was the P0300 which usually happened when my plugs were shot. Other than that, great gas mileage, perfect idle, tuned right, no knock, etc. Life was good.

Then I decided to "fix" things, went to 80lb injectors, zzp phenolic intake manifold spacer, dropped to the 2.8in pulley, added the zzp single pass intake manifold, and the ottp 4th gen heat exchanger. Other than the typical IAT issues I was fighting everything was ok, idle wasnt quite as good but it wasnt surging or anything like that. About two weeks ago P1101 pops up which is some sort of mismatch between MAF and MAP, I retuned again, didnt go away. I kinda ignored it because the car ran fine otherwise. I've started to have a P0496 code pop up every other day recently, thats something pertaining to EVAP, again didnt really have an impact on drivability. I did get a P2261 code pop up on sat night, so sunday I ripped off the charger checked the bypass valve, put it all back.

Then came yesterday morning, I turn on the car and it dropped to a real low idle and i had to push the pedal down to keep it running. Then it started ok, but idle seems to intermittently hang around 1200 now, about 1 out of 4 times when I come to a stop it actually idles at the proper speed. On a completely cold start in the morning it seems to carry on jumping the idle up and down for about 10 secs then clears up, never did this before.

I'm confused and its not really something I can take to a dealer because they will just throw their hands up and blame everything on the aftermarket parts and charge and arm and a leg. I can't figure it out, I can provide tune and log data from hp tuners if needed.

 

right off the bat I can tell you adding 33% to your fueling needs to be tuned for, your computer probably still thinks it should have 3.x ms or so of injector cycle when it should now be less. What does your AFR look like at idle and cruising around? You need to reduce your Injector PW by 33% your car's MAF calibration shouldn't need messing with at all with a smaller pulley, that sort of thing is for intake changes and MAF relocations. You need to go back to your original MAF that worked with your intake. Tune your pulse width down for the injector size and start over from there. I suspect the evap code and bypass code are from a vacuum leak either at the gasket or in the lines from the R&R on parts install. Go over everything closely, when I suspect something a shot of TB cleaner at the spot where it might be leaking (at the gasket) reveals it well enough when the motor changes cadence. Good luck and let me know.