Code P0503?

JAGRAVES2

MEMBER
2002 JEEP WRANGLER
4 CYL
4WD
MANUAL
90,000 MILES

Bumping and hesitating has lessened, but when idling the Jeep runs at about 2300 to 2800 RPM. Way up from the usual 500-700. I now get an error code P0503 for the Speed Sensor being erratic. I have looked through my Repair Manual and cannot find reference to a speed sensor. Is this the same as the throttle sensor? Can someone please help me identify what the new problem might be?

1 Reply

KASEKENNY

MECHANIC
18,907 POSTS

It is unlikely that this code is related to the erratic idle. If you have a high idle then that is most likely due to an air intake sensor or even a vacuum leak.

Here are a couple guides that we need to run through in order to figure this out:

https://www.2carpros.com/articles/engine-idles-too-high

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

Please let us know what you find with this info. Also, I attached the info below on the speed sensor. Please run through this info and let us know if you have questions. Thanks

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