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Derrick, ASE Certified Technician
Category: Jeep
Satisfied Customers: 923
Experience:  A.S.-Automotive Analysis A6-Electrical A8/L1-Engine Performance Cert., CA Chrysler/Jeep/Dodge Tech
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2001 Jeep Grand Cherokee: V8..intermittently..Cold start, engine runs

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2001 Jeep Grand Cherokee 4.7 V8: Idle speed is intermittently high after engine reaches operating temperature. Cold start, engine runs to 2000 RPM for about 2 to 3 seconds then drops to 1500 then drops to 1300 but surges between 1500 and 1300 RPM. After engine reaches operating temperature, warm start engine will run 1500 RPM for 2 to 3 seconds and then drop to 1000 RPM and then after about 20 seconds drop to 600 RPM. Intermittently on warm start engine will run at 2000 RPM and will not idle down. What causes intermittent high idle?

Hi there,


This is most likely a failed TPS (Throttle Position Sensor) or IAC (Idle Air Control) motor.

I would recommend performing a throttle body cleaning.

Next try tapping your IAC motor while your car is idling to see if it changes the idle. If so, you most likely have a bad IAC motor, if not it is most likely your TPS.


I hope this helps! Let me know if you have any more questions!

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