So what was your car doing before you inverted your Idle Air? Ill upload a data log and tune.On my car I had to set the IAC setting to inverted for it to start. Post your tune file so folks can go over it. Also, a cranking data log file.
Usually, its something really simple.
I was there too. Was ready to take a hammer to my mspnp2. I even contemplated selling the car. My issues stemmed from the IAC setting and a bad computer ground wire near the battery. Steve a91what jumped in and helped me out big time.
Don't throw in the towel yet. Lol