Idle Hunting

[ItsAnAdventure]

I had to drive our 91 MTX this past week while my pickup truck was in the shop for service. The idle is running high at around 1,200 until the engine has gotten good and warm (at least 15 - 20 minutes). Also, during the initial warm-up the idle hunts up and down when I come to a stop, finally settling at around the 1,200 mark.

I have not run codes yet. I'll have some time tomorrow to run those checks. Any thoughts????

Thanks,

 

[LOUDSHO92]

Clean the IAB or it needs to be replaced.

 

[shooff82]

I agree. But also sometimes indicative of a vacuum leak.

 

[rubydist]

Also check the thermostat or temp senders - if the engine stays cold (or pcm thinks its cold) it will keep the idle elevated for up to 20 minutes.

check the codes so we don't need to guess.....

 

[ItsAnAdventure]

Will run the codes in the next day or two. Thanks for the suggestions, I will also investigate them.