Anyone have bad cps that gave normal resistance reading?

I'm having some starting problems with the truck warm. I'm figuring it's either the ignition control module or the cps. I put in a spare ICM with no change. The cps I have reads 225 ohms resistance, about the same as another used spare I have.

My question is this....can a cps be faulty while still giving resistance readings in the proper range?

Cheers!

Yes. The no start/stallng problem is usually intermittent when the CPS goes bad so unless it's in "non-functioning mode", you won't pick up the resistance of infinity.
You said you're having warm starting problems. What about when the engine's cold? Any other symptoms before we blame the CPS?

the early xjs cps generate ac voltege so ohm testing isnt reliable. hook a digital volt ohm meter to the crank sensor plug on the ac scale. it should read close to 500. still probably a bad cps failing on hot restart, pretty common.

jneary said:

the early xjs cps generate ac voltege so ohm testing isnt reliable. hook a digital volt ohm meter to the crank sensor plug on the ac scale. it should read close to 500. still probably a bad cps failing on hot restart, pretty common.

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500 volts? Or 500 millivolts? Or 5 volts? What scale are you using?

On the renix pre 91s it should read from .5 to close to 1 volt. The pre 91 cps generates it own voltage. The post 90s non renix are a three wire w. 5 volts supplied by the ecu. The intermittnent failure while warm is usually caused by the wire harness connector going bad. The female side of the connector expands when the engine is very warm so if it is a little lose or corroded when it warms up and expands you lose the signal expecially given that less than one volt is involved. I rebuilt my connector internals and all is well. You can rebuild them or cut them off and replace w. another type of connector. Greg