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Topic: Bad idle quality (Read 1187 times) previous topic - next topic

Bad idle quality

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:

Re: Bad idle quality

Reply #1
Check your o2 connections,firing order,and vaccumm connections,all could be possible causes.

Re: Bad idle quality

Reply #2
check the hose going to the map sensor once i switched that hose for the one on the egr and had the same problem
95 Ranger Splash 2.3
88 Tbird Sport :ies::ies:
5.0 SO, stainless shorty headers, w/ Magnaflow lers. KYB struts, KYB shocks. 5lug conversion from sn95 Mustang, subframe connectors, drilled and slotted rotors, 03 Mach 1 wheels. sequential taillights.140 speedo

 

Re: Bad idle quality

Reply #3
My map sensor is now a BAP sensor with no vacuum line since the HO swap.