I have a 94 stock xj 4.0 trying to get it through deq and came hc at 3385 at idle, I replaced the idle air because idle was to high and replaced map and o2 sensor, still getting map error code 14. tested map and it is 5v on one side and when I add vacuum on to 20 output in center wire is1v seems to be working, why am i getting error code and running rough at idle now after replacing map?

 

Have you checked for vacuum leaks?

"Unplug the IAC and if it still idles then there's a leak.A pressure guage with a fixed duty cycle will fault find the injectors. Carb cleaner will clean throttle body. A partially plugged cat will give neg trims as not enough air for engine to breathe.measure back pressure at front o2 sensor. Graph tps on scan tool and look for irregularities.low compression will give neg fuel trims.wrong air filter will give neg fuel trims." Quoted from a youtube comment by Tom Oconnor.

 

first thing...pull vacuum line off the fuel regulator on the front rail ...make sure its not wet with fuel..... when it is running does your cruise control work or is your blower always on defrost...the canister in the front rt bumper might be broken or loose connection causing vacuum leak..follow the lines from all your manifold vacuum points sometimes the rubber connectors come off or the hard lines crack