Topic: Very high idle

[Moose95yj]

I have a 95 wrangler wiht a 2.5 4 cyl.  once ipush my clutch in i am seeing idle speeds as high as 3500 or asl low as 1700.  i have changed my iac motor replaces my vacume lines.  What else should i check. 

[aw12345]

vacuum leak?

[Tsd]

Could be the o2 sensor, did you check for codes?

[warpedredneck]

vac leak? stuck egr? o2 doesnt usually drive the idle high(but its possible), throttle body base gasket(leaking)
all i can think of right now

[jfrabat]

I have a 95 wrangler wiht a 2.5 4 cyl.  once ipush my clutch in i am seeing idle speeds as high as 3500 or asl low as 1700.  i have changed my iac motor replaces my vacume lines.  What else should i check. 

Sounds like either a vacuum leak or a IAS sensor...  Check not only the sensors, but also the connections.  Also check the screw that limits the throttle plate on the TB; could be adjusted wrong.

Have you done the 4.0L TB conversion?  If so, did you use the 2.5L IAS motor and housing?  When I did mine, I forgot to do this, and the idel went way up...

stuck egr?

As far as I know, there is no EGR on the '95...  (I have been wrong before, though!).

[Moose95yj]

OK there is no egr on the 95.  As far ar the eacume leaki cant not find one and i have changed the tb base plate gasket.  can you tell me more about the iac sensor.  The only thing myhays book showed was the motorits self. 

[jfrabat]

OK there is no egr on the 95.  As far ar the eacume leaki cant not find one and i have changed the tb base plate gasket.  can you tell me more about the iac sensor.  The only thing myhays book showed was the motorits self. 

I meant motor, not sensor...  But check that the housing says 2.5L, as if you have the 4.0L housing (unlike the 2.5L, it does not say anything), the idle will shoot up.  It could also be the motor itself that is stuck; try removing and cleaning it (or replacing it).

[jcd1026]

could the iac motor also cause stumbling at low rpms?  Or a cold start lope?

[Jeffy]

could the iac motor also cause stumbling at low rpms?  Or a cold start lope?

If the engine isn't warmed up enough to bypass the IAC then the Jeep won't idle for crap.  IIRC, the engine will die if you don't apply some pedal.

[jcd1026]

If the engine isn't warmed up enough to bypass the IAC then the Jeep won't idle for crap.  IIRC, the engine will die if you don't apply some pedal.

I've never had to use the pedal before, I've had it running well for the last 6 years.
Thanks for the reply, I've started a new topic for my problem.

[Jawbonz]

Check to make sure the manifold bolts are all there.  I replaced my water pump a few years ago, and it was just enough jarring that the missing #4 bolt on the intake manifold became an issue. It peeled away just enough to cause a 0-5000RPM run as soon as the motor cranked.  I didn't even know the bolt was missing.  Replaced it and the problem was gone.