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1997 Jeep Grand Cherokee Question: idle speed

 

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laker78, 4.0L 6 Cylinder, Shelbyville, KY, March 17, 2009, 01:32
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what is the normal idle speed for 1997 jeep grand cherokee and can the idle speed be adjusted.my jeep is idling at about 400 RPms after it gets warm.

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  • Answer #1

    Andy Y March 19, 2009, 12:35
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    Your idle speed should be shown on the emissions sticker under the hood (it will also have spark plug gap if it's like my 4.0 Wrangler). I don't think there is any adjustment but something really common on Jeeps is the throttle body gets plugged up with carbon buildup.

    The black, oily buildup closes off the throttle opening causing the low idle and maybe stalling on braking. Pull off your intake tube and check the throttle bore and throttle blade for buildup (it will be black and caked on there). The bore should be the same raw metal finish that is on the outside of the bore (ie. not black). Spray some throttle body cleaner on a shop towel and start scrubbing the throttle bore and edges of the throttle blade. If it's never been cleaned, it will take some elbow grease and do NOT spray directly on the throttle body because the cleaner might damage sensors on the throttle body. hope this helps!

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