86 idle issue

[danger ranger 86]

my 86 seems like to idle where ever it wants to, it did have a broken vaccum line but that has been fixed. it also has an exhaust leak which i will be fixing this week but i don't think has anything to do with the problem. so anyone have any ideas on where to begin or what might be causing this issue? btw it usually idles between 2200 and 3000 rpms and when it does come down it idles below 1k sometimes below 800 and stumbles.

 

[IMenriched]

my 86 seems like to idle where ever it wants to, it did have a broken vaccum line but that has been fixed. it also has an exhaust leak which i will be fixing this week but i don't think has anything to do with the problem. so anyone have any ideas on where to begin or what might be causing this issue? btw it usually idles between 2200 and 3000 rpms and when it does come down it idles below 1k sometimes below 800 and stumbles.

Clean and or replace the IAC (Idle air control)

best to get codes, in case other issues are a foot.

 

[Spitfire1975]

^^^agreed. Also, check behind the throttle body. There is a hole/port that goes to the EGR that can get plugged with carbon. Make sure that is clean and the EGR sensor position and EGR itself is good. Check the Throttle position sensor (backprobe wires - volts should be around .95-.98)

 

[Spitfire1975]

http://therangerstation.com/forums/showpost.php?p=183814&postcount=17 Code tester

http://www.therangerstation.com/tech_library/OBD_I.html Code test procedure

 

[Epixstar]

just go out and buy a few feet of vacuum line and slowly replace one at time. Some times this cheap fix can work wonders but if not at least you know they are all new.