I have the following idle problem in my 85 22REC Runner:

1. Will NOT idle - when reving I can here a "relay" clicking on and off near the front right of vehicle.

2. Drive on highway 10-20 miles - problem goes away - idles like a dream...

Any thoughts where to check 1st???

Thanks in advance!

 

Likely the circuit opening relay is wat you are hearing, it is in the passenger side kick panel area. It is turned on and off by the ful pump switch in the air flow meter. Might be having a problem with that casuing the problem.

A quick way to test this:
- http://www.4crawler.com/4x4/CheapTricks/index.shtml#MODIFICATION$$$

Check out the AFM:
- http://www.4crawler.com/4x4/CheapTricks/AFM/index.shtml

Or it could be the CO relay itself acting up. If the FP test jumper works fine, that is one option, i.e. leave the jumper in, another option is to replace the CO relay (~$100).

 

Thanks 4Crawler! I will give it a try...

 

If that does not do it and you have EGR, check the EGR VSV's

EGR is not supposed to be injected into intake manifold/plenum at idle if the VSV's misbehave and you get EGR at idle it will make speed very erratic and probably not let it run.

After vehicle warms up, one or more sensor may function correctly.

David