ok so recently my 3.1 is running like a POS and doesn't idle very well, and its always backfired out of the digital egr when goosed, i have replaced my IAC,TPS,MAP,O2 sensors and i'm still getting a code 22 thrown everytime i get in the car, how ever i got a wild hair and unpluged my EGR and my idle smoothed out why would that make a difference (i didn't drive it becuase i didn't have any gas to just test)how ever it idles high at about 2k..........got any ideas? i'm thinking my ecu might be bad, i know that before i bought it there was some custom chip burning done to it could that be the source?

 

Sounds like a vacuum leak

 

Sounds like you have a bad EGR valve signal. The valve itself is spring loaded closed, so if the wires get broken or something, the thing closes and you'll still have a smooth idle and so on. This takes car of any drivability problems. The custom chip work might be to blame on this one. If someone screwed up and made the egr open a little at idle, or changed a certain parameter that makes the computer think that you need EGR at idle, that's where it's coming from.

I bet someone messed with the TPS parameters. The ECM expects a certain TPS voltage for a certain RPM range. Now, if they reprogrammed the ECM to think that it's off idle all the time, you would get a code 22 (Low TPS voltage) and the ECM would command a certain EGR duty cycle.

I say look for all the obvious stuff, like vacuum leaks and bad connections, then if all that checks out, see if you can get a hold of a stock chip and see if it fixes the code and the EGR problem.

Hope this sheds some light on the subject.

Jeff