96 cherokee turns over but no start

[85xjwoody]

"The PCM monitors the crankshaft position sensor. If the PCM does not receive a crankshaft position sensor signal within 3 seconds of cranking the engine, it will shut down the fuel injection system."
are you sure the pump isn't coming on at all?

I am sure the pump is not coming on at all. As said before, the pump works when you jump the fuel pump relay but not any other time. I always heard the pump as soon as I turned the key on.
Now I don't hear it, don't have any fuel pressure, don't have any spark at the plugs, no power to the coil, just plain nothing.
Having a dead cam position sensor would that have any affect on no power anywhere?

Kim

 

[McQue]

this is starting to sound like a dead ASD relay...or no power to it...
You checked all the fuses in the PDC and in the Junction Block also...right?

 

[RyanM]

It's been a month and you haven't tried a new CKS????? If it aint it, keep it for peace of mind, or return it and say it's the wrong one, goin to Napa 4 out of 4 xj's in my extended family have had failed CKS' at around 125K, the no fire, no fuel scenario.

 

[85xjwoody]

CKS is a new one to me. Please expain. And yes, it has been a month. To damn cold to wrench outside.

Kim

 

[85xjwoody]

this is starting to sound like a dead ASD relay...or no power to it...
You checked all the fuses in the PDC and in the Junction Block also...right?

Just rechecked all of the fuses in the Junction Block and PDC. All good. I swapped out all relays in the PDC and still no go.

Kim

 

[RyanM]

sorry crankshaft positioning sensor. I hear ya, I thought you had been trying to tackle it for 30 days

 

[85xjwoody]

Looks like I will be getting a new cps tomorrow. This is going to be a bitch to replace. Gonna have to pick up some brew on the way home tomorrow.

Kim

 

[RyanM]

If there is no lift on the truck yes. It's a bitch. you'll need enough extensions to go back to the Xmember, unless your lady hands can fit between the bellhousing and firewall Don't drop the bolts in the bell and make sure you get the new one flush/lined up well.

 

[85xjwoody]

If there is no lift on the truck yes. It's a bitch. you'll need enough extensions to go back to the Xmember, unless your lady hands can fit between the bellhousing and firewall Don't drop the bolts in the bell and make sure you get the new one flush/lined up well.

Plenty of lift on the jeep so hopefully that helps. One thing that still bothers me though is how would a bad cps cause the fuel pump to not kick on when I turn the key on?

Kim

 

[ILLXJ]

Looks like I will be getting a new cps tomorrow. This is going to be a bitch to replace. Gonna have to pick up some brew on the way home tomorrow.

Kim

It only took me about 20 min. to change it. I could reach up & get to the bolts from underneath. I don't even think I had to use an extension like most say they do. JIM.

 

[ILLXJ]

Plenty of lift on the jeep so hopefully that helps. One thing that still bothers me though is how would a bad cps cause the fuel pump to not kick on when I turn the key on?

Kim

I don't remember where I saw it, but I read that the CPS can short out inside. It then shuts down the computer so it doesn't fry anything else. Don't know if it's true, but it makes sense. JIM.

 

[RyanM]

Didn't read anything in this thread about Spark, are you getting it? I'm pretty sure once the key is 'on' if there is no pulse from the sensor, then the pcm will shut down everything except the starter for some reason.

 

[85xjwoody]

No sparky anywhere. Just wanted to say thanks for all the help! Electrical and me don't get along so good just yet. I am still getting used to the newer style jeep.

 

[Powderhound]

I just replaced my CPS this evening. I did it with a 7/16 long socket, my 1/4 drive with a 6" extension, and a universal/wobble joint on the drive. It made the job pretty easy. Good luck!

This is also a pretty cool idea:

http://www.floridajeepers.net/viewtopic.php?t=20947

 

[85xjwoody]

Not so good of luck yet. Replaced the CPS and tried to start it with the same results. Did I miss something? I don't think so but you never know. Changed the relays again and still no go. WTF is up? This sucks.

Kim

 

[85xjwoody]

Just checked for spark and no go. Still no pump kicking on. Do I need to disconnect the battery and leave it for a half hour or so to reset the computer? Maybe that will help.

Kim

 

[89xj]

Just checked for spark and no go. Still no pump kicking on. Do I need to disconnect the battery and leave it for a half hour or so to reset the computer? Maybe that will help.

Kim

doubtful.

 

[85xjwoody]

I will give it a try while I look at a few other things. Don't really know what I am looking for but time to investigate.

Kim

 

[RyanM]

It's starting to sound like a mystery on a YJ my buddy and I were trying to figure out. Never did and it was turned into a stroker for another project.
I can't think of anything else ASD?

 

[85xjwoody]

It's starting to sound like a mystery on a YJ my buddy and I were trying to figure out. Never did and it was turned into a stroker for another project.
I can't think of anything else ASD?

Swapped the ASD relay and still no go. If this mystery goes on much longer I will just strip everything off of this pile and build another one.

Kim