Most of the time if the wiring or settings are wrong you will get a code like maybe ...31 for maf signal missing. the car will still run though. I set mine up like it says on mkiv.com, and Changed all the Ne points to >4000. The knock wire I didn't connect since that data is pretty much useless, and one more hack into the ecu harness. If your rpm reading is accurate, that means the power ground and rpm signal are correct, hell the only other thing is the Maf wire and TPS, just make sure that they are going the right way to ecu and sensor. I have my lo throttle set at 10%, and Hi at 80, No correction values for less than 4k and no corrections for lo throttle... Good luck I'm not an expert on this thing yet, but this is what I found.