JeepcoMJ Posted March 23, 2009 Share Posted March 23, 2009 any ideas what could cause a renix 4.0 to not idle past 3500? it acts like that's its limiting rpm. it's an 87 4.0 with auto. I've swapped ignition pack, engine computer, tranny computer, MAP, and throttle bodies still the same. leaning towards bad CPS? Link to comment Share on other sites More sharing options...
Eagle Posted March 23, 2009 Share Posted March 23, 2009 Idle speed for the 4.0L is 650 RPM. What's this about 3500 RPM "idle"? Link to comment Share on other sites More sharing options...
Pete M Posted March 23, 2009 Share Posted March 23, 2009 I think he means that it won't rev higher than 3500. :D Did this come on suddenly or gradually? Link to comment Share on other sites More sharing options...
Geonovast Posted March 23, 2009 Share Posted March 23, 2009 Bad ECU? Link to comment Share on other sites More sharing options...
HOrnbrod Posted March 23, 2009 Share Posted March 23, 2009 Not sure if this will help in your Renix case, but a guy over on the Strokers forum had the same problem - turned out to be a mis-indexed distributor. http://www.jeepstrokers.com/forum/viewtopic.php?f=15&t=568&hilit=limited Link to comment Share on other sites More sharing options...
JeepcoMJ Posted March 23, 2009 Author Share Posted March 23, 2009 I think he means that it won't rev higher than 3500. :D Did this come on suddenly or gradually? yes, won't rev that far. idles at 650rpm tho. new ecu made it run better. Bad ECU? as stated, already swapped it out. not the problem. Not sure if this will help in your Renix case, but a guy over on the Strokers forum had the same problem - turned out to be a mis-indexed distributor. http://www.jeepstrokers.com/forum/viewtopic.php?f=15&t=568&hilit=limited thanks hornbrod...I hadn't even thought of that. that's pretty likely actually, knowing who worked on it previously. just pissed I didn't notice the problem 2 years ago when I originally bought the truck (it's passed through two friends since then) -Pat Link to comment Share on other sites More sharing options...
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now