Three weeks ago my 87 XR7 with the HO was running like it came that way from the factory. Perfect idle. Then I pulled the engine to install the B&M 2400. Out and back in in one day, no snags, everything went smooth :D . The idle sucked as soon as I started it back up, but I thought I'd give it a long while for the computer to adjust after being unplugged for several hours. Well, it still idles like it has a big cam in it :yuck: . Not cool since it doesn't have a big cam. The converter was the only change. I ran a self test and it didn't come up with anything that it didn't show anything that it didn't have before (due to the HO swap). So the only change is the converter which shouldn't hurt idle quality. I rechecked the TPS - .98, and nothing else was even touched anyways. Could a hidden vacuum leak make it idle like this. As soon as I'm off idle, it runs like a champ. Smells very rich at idle too. Any suggestions?
BTW it launches great now. :canada:
Check your o2 connections,firing order,and vaccumm connections,all could be possible causes.
check the hose going to the map sensor once i switched that hose for the one on the egr and had the same problem
My map sensor is now a BAP sensor with no vacuum line since the HO swap.