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General Forums => The Mess Hall => Topic started by: cabz on July 21, 2007, 07:03:59 AM

Title: Idle return at stop
Post by: cabz on July 21, 2007, 07:03:59 AM
Hello
I have been haveing a problem with the ole YJ lately, whenever I hit the clutch as I am rolling to a stop the idle drops way down . it used to drop down to about 1200 rpm untill the heep stopped rolling then it would drop down to ide speed .
this has been an on again off agian problem that I cant seem to figure out . I have had the jeep on a scanner and cant find anything wrong.
any ideas?

By the way it's a 92 YJ 4banger 5spd :smile:
Title: Re: Idle return at stop
Post by: jfrabat on July 21, 2007, 07:32:33 AM
My 4 banger acts more or less the same way, but i do have noticed that the hotter the day, the more the iddle drops.  Still, it never quits, so I just leave it be.
Title: Re: Idle return at stop
Post by: Bounty Hunter on July 21, 2007, 03:48:25 PM
Does your speedo work?

A speedo not working will cause that, as well as a bad/dirty IAC motor on the throttle body.  The TB can usually benefit from a good bench cleaning.
Title: Re: Idle return at stop
Post by: jfrabat on July 23, 2007, 04:34:06 PM
In my case, the speedo is working fine (actually, I just changed the gears to 38 when I finished the SYE last weekend), and the TB I cleaned in January when I tried to do the 4.0L TB install (at that time, I even thought the reason the 4.0L was not adjusting the idle correctly was because of the sensors, so I bought new ones; although it still did not idle correctly, I left the new ones in on the 2.5L throttle body - I think the reason for the bad idling is that there is some corrosion on the side of the TB which lets air through).

Felipe
Title: Re: Idle return at stop
Post by: cabz on July 23, 2007, 07:02:05 PM
Nope the speedo is working and I have cleaned the TB  a while ago , I might just replace the IAC . this is an on again off again problem  it seems to come and go with no real pattern.

Some time though the idle will get real low and kinda rough .
I think my injectors have about had it
Title: Re: Idle return at stop
Post by: Jesse-James on July 24, 2007, 01:36:50 AM
I had that problem for a while after my TB swap. Cleaned out the IAC with some carb cleaner and it smoothed out.