Cps question

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Nov 7, 2025 | 05:08 PM

Dan V

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From: north of Minneapolis, MN

Cps question

On a 2001 does the tach move or not if the cps is bad?

Nov 7, 2025 | 07:51 PM

BWST

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From: Lake Stevens, WA

if the CPS is good on a 99 to 01, the tach will move during cranking. If it’s bad, the tach will not move.

Nov 7, 2025 | 08:51 PM

Pikachu

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From: Amarillo, TEXAS!

The most reliable way to tell is monitor the RPM PID with a scan tool.

Nov 7, 2025 | 09:27 PM

Sous

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From: Lake Hartwell, GA

Quote:

Originally Posted by Pikachu

The most reliable way to tell is monitor the RPM PID with a scan tool.

This is accurate! I had an intermittent CPS failure on my 2000 PSD and the tachometer would appear to move a bit. Although, on the PID displaying RPM, it was a noticeable difference from where it should have been. The CPS would sometimes cause a no start or a start and run for a short amount of time or a start and run for an extended period of time. This happened to us 600 miles from home while towing the 5th wheel. Luckily my wife thought of the idea to use a butter knife to pry the CPS out of the block otherwise I might be in the ditch still checking my back for gators.