bbrasee

Well, ever since we bought my fiancee's 98 cherokee this spring, the check engine light had been on with misfires on 3 and 4. It would flash, it would stay on, it would go off.

Symptoms were: hard start, rough shut-off, and a rough idle, it felt like (never driven another cherokee or straight-6 engine vehicle, so nothing to compare it to.)

I replaced all plugs/wires, nothing. I didn't mess with ohm-testing any of the injectors, I assumed 4 injectors wouldn't go bad all at once, and the fuel pump sounded normal, and the engine is super clean and only has $90k on it.

just checked the code reader again and it came up as FOUR cylinders misfiring now, not just the original 2.

I just decided to take the plunge on a $50 CPS and see where that left me... and voila. I only took it for a little spin but it starts up smooooooth (no more cranking the starter for 3 seconds) drives great and the shut-off is as quiet and smooth as can be.

If you've got similar issues and are at a loss, I'd recommend starting by replacing this... you can get a $60 mopar OEM crank sensor from e-bay. I guess they like to go bad after 100k mi or so anyway....


And people are wrong who say the CPS either works or it doesn't, as if there's no in-between. from my experience they can definitely fail gradually.

Time will tell if any other issues remain. Just thought I'd throw this out there for anyone who might have a similar case.

Radi

Nice work! And thanks for the confirmation that the CPS isn't an all-or-nothing failure.

99rockies

Having a hard time removing the cps. Did you have to remove the passenger motor mount to pull it?