claygrassmann

how often does a cps usually go out? will excess mudding cause them to go out faster? what about water damage can excess water make them go out sooner? im gonna be gettin the relocation kit at some point im just wondering how soon my new cps is gonna go out.

mycherokee1989

I've heard that it should be changed like every 20, 000 miles or something, but I think that is crap. I've had my original one with the jeep at 230 000+ miles and just recently changed it for a new one, because the wires looked bad, but I noticed no difference in how the car started/ ran.

There is also no good testing procedure for it. In my haynes manual there is a testing procedure, but It only shows you if it works, or if it doesn't. There is no middle ground for the test.

5-90

I'm told that RENIX CPS units go out ~180Kmiles, and experience seems to bear this out more or less. I'm not sure about later units (they're a different sensor, working on the Hall Effect principle,) but they seem to run a bit longer.

Whoever told you 20Kmiles needs to go soak his head, 200K is a bit more believable. It's running in a warm environment (a few inches from the #6 primary tube, and in a sort of "dead spot" for cooling airflow,) but it seems to be built with that in mind.

Playing about in the wet (water/mud) doesn't seem to faze it much, so that's not a worry.

And, while there's no middle ground for the test of the CPS (I think the FSM is a GO/NO GO test as well...) there's not a lot of middle ground for CPS function either - it either do work or do not work. If it do not work, it do not work (I've seen one fail due to an external cause - the wiring got loose and shorted out on the #6 primary tube. That is the only intermittent CPS I've seen or even heard of - while I've heard of two other cases, I gave them the advice to do a visual on the wiring and that turned out to be it. All three were repaired using a segment of 18/2 SJOOW and some heat-resistant sleeving over the wiring.)

mycherokee1989

Yeah they said that they replaced it whenever they replaced the fuel filter or something. I'm not 100 percent sure on the number they used, but it was kinda stupid. It was one of those guys who throws parts at his jeep rather than locating the problem.

syncview

warning: THREAD HIJACK :P :Is there anything aftermarket or maybe from some another car, that can be used to replace the CPS?

claygrassmann

advance adapters makes a set up that relocates it by the harmonic balancer but its 250

Metmknice

Best thing to do is check it every so often. Like when you do a repair or change your oil. Can be done easily if you have DVOM/DMM

JeepingDan

I can't see water or mud messing them up because their sealed. Unless it has a crack in it. I have 177k on mine and it's still going. I'm gonna get a spare to keep in the xj just in case though cause getting stranding in noware sucks.

xj2000

Pardon my ignorance but what is CPS?

Mattster

CPS = Crank Position Sensor.

greenjeep23

Where is it located? I know it's somwhere on the bellhousing but not sure excatly.

4xPhil

Is the CPS difficult to replace?

4xPhil

I am getting an error code showing CPS failure and misfire in #1.

Hard starts when hot, usually when slow crawling for awhile.

What are the indications for the CPS going out?

Would that cause the code of misfire?

Thanks

G_P

Mine has 220k on it and AFAIK it is stock. they work on magnetic signals so they are fully sealed and water should not affect them unless it finds its way into the wiring harness and shorts it out there or there is some kind of damage to the wiring.

They are just one of those sensors that could last forever or will just up and die for no good reason at all. so far the only CPS that i have seen die was on an Odlsmobile 3.8L.

5-90

CPS failure is typically a case of "Crank, No Start." The engine will crank all day long, but it won't get the base signal used to set fuel injector firing and ignition timing.

Go through the rest of your ignition system to diagnose a single-cylinder misfire - start with the plug wire and possible contamination of the plug gap. Also check the resistance of the centre electrode, compare it to two or three other plugs in the set (honest - I've seen misfires caused by things like that! Not on OBD-II - so I had to do my own thinking to establish that it was a misfire... But, with OBD-II, at least you can start looking on the right cylinder.)