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  #1  
Old January 24th, 2017, 09:23
Forestgreenxj Forestgreenxj is offline
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01 Jeep only Starts After Sitting

So I just bought my first xj its an 01 and it only started after sitting for about 8 hours and I replace the CPS and now it wont start at all, butt will crank and crank and crank, any help would be appreciated
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  #2  
Old January 24th, 2017, 09:48
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dan1977p dan1977p is offline
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Re: 01 Jeep only Starts After Sitting

Put your good CPS back in first to get back to a running condition.
Then put this into google and have fun: jeep xj wont start when hot
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Old January 24th, 2017, 11:11
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Re: 01 Jeep only Starts After Sitting

Test the fuel pressure. Test the check valve leak down. If the fuel pressure is correct, suspect the Crankshaft Position Sensor (CPS) or its wire plug and wiring. Wiggle and inspect all the wire harnesses and wire plugs. Look melted/chafed insulation and corrosion.

Cheap Chinese CPS, often sold with a "lifetime Warranty", are well known to be out of specification or even failed right out of the box. Only buy genuine Jeep engine sensors.
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Quote:
Originally Posted by bimmerjeeper

Blanket caught in the rear liftgate latch. Now I can't open.
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Old January 24th, 2017, 11:14
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Re: 01 Jeep only Starts After Sitting

there has been people that have gotten bad parts out of the box. i would try a better quality one.

once it gets running does it stay running and run smooth?
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Old January 24th, 2017, 19:25
Forestgreenxj Forestgreenxj is offline
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Re: 01 Jeep only Starts After Sitting

I have fuel at the rail I pressed the valve and fuel sprayed out, and when she starts up she runs like a dream. And the replacement CPS was from autozone.

Last edited by Forestgreenxj; January 24th, 2017 at 19:30.
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Old January 24th, 2017, 20:03
md21722 md21722 is offline
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Re: 01 Jeep only Starts After Sitting

Quote:
Originally Posted by Forestgreenxj View Post
And the replacement CPS was from autozone.
Quote:
Originally Posted by Tim_MN View Post
Cheap Chinese CPS, often sold with a "lifetime Warranty", are well known to be out of specification or even failed right out of the box. Only buy genuine Jeep engine sensors.
Get one from Mopar.
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Old January 25th, 2017, 05:53
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dan1977p dan1977p is offline
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Re: 01 Jeep only Starts After Sitting

Do CPS's fail when the motor is hot? I didn't think so. That's why I suggested the search I did. Everything suggested so far seems like the opposite of his issue. Unless I read it wrong, it starts fine the first time but has to sit for eight hours to start again. I bet it just needs to cool sufficiently to make one of the sensors on the intake start working again. Or maybe the wiring to the CPS has sat on the exhaust header and now is toast.
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Old January 25th, 2017, 11:25
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Re: 01 Jeep only Starts After Sitting

Crank Position Sensors can have intermittent “thermal failure”. This means that the CPS/CKP fails when the engine gets hot, but works again when it cools back down.

The root cause may in fact be something else, but so many "Lifetime Warranty" CPS have been total crap that the CPS cannot be ruled out as the primary cause until it is genuine Jeep part.
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Quote:
Originally Posted by bimmerjeeper

Blanket caught in the rear liftgate latch. Now I can't open.
.

Last edited by Tim_MN; January 25th, 2017 at 11:28.
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Old January 25th, 2017, 14:24
Forestgreenxj Forestgreenxj is offline
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Re: 01 Jeep only Starts After Sitting

Just bought a mopar cps, and returned the autozone one, we'll see how this goes.
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Old January 25th, 2017, 15:14
Forestgreenxj Forestgreenxj is offline
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Re: 01 Jeep only Starts After Sitting

Just installed my mopar cps it coughed but didn't start, still smelled fuel in the intake so Im thinking spark.
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Old January 25th, 2017, 16:28
Forestgreenxj Forestgreenxj is offline
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Re: 01 Jeep only Starts After Sitting

Just bought a scanner and its telling me camshaft sensor
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Old January 25th, 2017, 16:28
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Re: 01 Jeep only Starts After Sitting

With the CPS ruled out as the primary cause, a faulty Cam Sensor would make a likely suspect, especially if you have a related trouble code.
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Quote:
Originally Posted by bimmerjeeper

Blanket caught in the rear liftgate latch. Now I can't open.
.
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  #13  
Old January 25th, 2017, 20:26
Forestgreenxj Forestgreenxj is offline
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Re: 01 Jeep only Starts After Sitting

I just replaced the cam sensor with a mopar parat and she started right up! Thanks for all the help guys!
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