Join Date: Apr 2002
Thanked 3 Times in 3 Posts
YJ idle oddity.
Did a search, couldn't find anything relating to this...
But here's the deal, it's not a really important problem, but more annoying than anything. I have the timing set to 10 BTDC @ 1600RPM (spec is 9 +/- 2), Vacuum kick idle is set at 1150RPM (Spec is 1100 +/-50) Vacuum solenoid is set at 975 (spec 900 +/- 50) and curb idle is at 750 (spec is 680 but don't remember wat tolerance is allowed, I think it my be 80).
It idles at those RPM's when cold as verified by a handheld tach, but as soon as it warms up (coolant temp over 180 or 190) it will idle at 1150 for about 5 - 10 seconds, will then bypass vacuum solenoid and curb idle and will idle at around 350 - 400.
I've had the hood up and watched it idle like that. You rev up the engine to say 3000, then let it drop. It will then idle at the 1150 I have the vacuum kick set to. While the uppermost adjusting screw (the one that contacts the vacuum solenoid plunger) is still touching the plunger, the idle will drop down to around 400.
The fast idle screw never comes in contact with the idle cam when, nor does the curb idle screw come in contact with the carb. body the whole time.
When I had the carb apart, I did notice that the bowls were a little less than half full, could the idle oddity be caused by not enough fuel in the bowl, or is there something else I should check out?
Only happens when engine is warm (over 180 degrees)
Does this air cleaner on or off.
Carb was rebuilt 2 weeks before I bought the Jeep back in April, was thouroughly cleaned a week ago.
No misfires, all plugs have the normal tan color to them.