Surging, rough idle, full throttle to drive?

2005 JEEP GRAND CHEROKEE

160,000 MILES • 4.7L • V8 • 4WD • AUTOMATIC

MIKEYUSMC

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Start car (fires up nicely) let it warm up until idle falls to 600 RPMs (30-45 seconds) put it in gear it instantly starts surging like 300 up to 700 RPMs. Try to take off smoothly but car jerks violently unless I punch it. Then it drives like hell until I ease of the throttle. But it goes back to surging.

Dec 24, 2022 at 11:10 AM

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Do you have a check engine light on? If so, we need to get the codes to guide us in the right direction for the repair.

This guide will help you:

https://www.2carpros.com/articles/checking-a-service-engine-soon-or-check-engine-light-on-or-flashing

If not, it sounds like you have a vacuum leak or the MAP sensor that is bad. Use this test when the engine is cold only.

https://www.2carpros.com/articles/how-to-use-an-engine-vacuum-gauge

Here is the location of the map sensor so you can check it out and replace it if needed. I have also seen the TPS cause this issue as well. Check out the images (below). Please let us know what happens.

Images (Click to enlarge)

Dec 26, 2022 at 9:37 AM