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Unread 10-30-2010, 08:53 AM   #1
96-XJ
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Idle Issue

The jeep is having an issue with high idle. in neutral or with the clutch in, it will rev between 1500-2500rpm and then slowly go down. When in goes back down to normal idle below 1000rpm and i hit the gas it gets muffled at first.

My first impression was a vacuum leak some where but nothing visual or by hear. I know that there's a sensor on the throttle body, but i dont think this is the right symptoms to be a sensor issue, plus theres no check engine. what gets me is that it drives fine cold, but once it heats up it get worse.

Any ideas

Thanks in advance

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Unread 10-30-2010, 09:23 AM   #2
ChicoXJ
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Since it changes rpms, that indicates that you have a problem with your idle air controller. It probably just needs to be cleaned. Remove it and clean with carb cleaner and it will probably be OK
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Unread 10-30-2010, 09:25 AM   #3
96-XJ
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thats the sensor?
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Unread 10-30-2010, 10:44 AM   #4
CJ7-Tim
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Cleaning the Idle Air Controller (IAC) :

Purchase sensor safe Throttle Body cleaner spray.

1. Remove the Throttle body from the intake manifold.
2. Remove the IAC with a TORX 15 driver (2 bolts)
3. Gently wiggle out the IAC from the throttle body
4. Clean the IAC with Throttle Body Cleaner (not carburetor cleaner). Use cleaner, a rag, and a toothbrush. Be gentle; donít twist or pull on the pintle as it is fragile and can be damaged easily
5. Also clean where the IAC seats in the throttle body with the same throttle body cleaner
6. While you have the Throttle Body off, give it a good cleaning also.
7. Reinstall IAC, the Throttle body, and check idle quality.

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Unread 10-30-2010, 11:27 AM   #5
96-XJ
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Great thanks a lot. I'll try it out Monday when i get back home
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Unread 11-01-2010, 10:58 AM   #6
96-XJ
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cleaned the whole throttle body this morning with throttle cleaner, to no prevail. The issue has gotten progressivly worse, now having issues starting. It will turn over for 10-15 and then finally start but very muttered. I also hear a slight raddling when in gear and driving but not when idleing. a couple times it's stalled when in neautral and i get a cloud of smoke in the engine bay i hope it isnt a valve or somthing

I know its a lot, i appoligize. Figure i might as well be describive to hopefully get the right diagnosis.
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Unread 11-01-2010, 05:58 PM   #7
96-XJ
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anybody???
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Unread 11-01-2010, 06:10 PM   #8
kbad
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hey man....perhaps you need to replace the IAC...it could be bad since the cleaning did not help!... good luck!
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Unread 11-01-2010, 06:21 PM   #9
cruiser54
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Using the same oxygen sensor safe throttle body cleaner you used earlier, spray around the intake and all vacuum lines with the engine running. You'll know when you find the vacuum leak.
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Unread 11-01-2010, 07:33 PM   #10
96-XJ
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Quote:
Originally Posted by cruiser54 View Post
Using the same oxygen sensor safe throttle body cleaner you used earlier, spray around the intake and all vacuum lines with the engine running. You'll know when you find the vacuum leak.
yes i did that earlier with starter fluid, no leaks...

I ran a volts test on the MAP sensor which seems to be the problem as the volts arnt changing with open throttle. Ill replace tomorrow and that will hopefully slove the problem
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Unread 11-01-2010, 08:29 PM   #11
ChicoXJ
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Then you probably just need a new IAC
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Unread 11-04-2010, 11:42 AM   #12
96-XJ
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Replaced the senor to no solution. i played around with the wiring harness and found that one the boots wasnt down all the way, must have been creating a short... runs good now
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Unread 11-04-2010, 04:57 PM   #13
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Connections before components.
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