Micah

I'm new here and I'm no mechanic, but I thought I'd ask. My Cherokee just died as I was pulling in the drive. It started back up for a few seconds but was extremely rough. Now it wont start at all. It will fire, but no start. I have been reading and from what I can tell it could be the O2 sensor or the CPS. So basically where do I start?

99WhiteLightning

check your fuel pressure your pump may have died my 99 is dead this is what mines doing

Micah

I just got in from trying it again, and I smelled fuel after I cranked it. It wonteven fire now. I assume since I'm smelling fuel that te pump is fine.

tjwalker

The strategy for a no-start should always be the same.

#1 is to verify if you have spark and if you do, if you have "quality" spark.

Pull a spark plug, keep it attached to the plug wire, place the spark plug electrode near a good engine ground, have a buddy crank the engine while you watch. You are looking for a strong, blue, snapping spark. Yellow/orange/white indicates a weak spark, which may not be strong enough to do the job.

If spark is good, spray a small amount of starting fluid into the intake or a small splash of gas. If it starts and runs good momentarily and then stalls, you have confirmed a FUEL DELIVERY problem.

Once you know what the problem is.....spark, or fuel.....the suspect list gets a whole lot shorter.

Report back your results.

Micah

Did the spark test. No spark at all. Pulled the coil and took it to autozone. I dont know if the guy knew wat he was doing. Pulled a new one off the shelf and it tested the same though.

Dakota5605

CRANK POSITION SENSOR

Dakota5605

Me and my son both have XJ's and when off roading we always carry a spare. Have been caught without it one to many times

dlracer73

Sounds just like mine when the CPS went. The mechanic that did mine showed me how to check the CPS. Have a buddy turn the key with the senor connected and keep your head by the relays and if you hear nothing unplug the CPS and do it again if you hear a click then it's your CPS!

Micah

The CPS seems almost impossible to get to. Any secrets to getting that bad boy out?

Thanks for all your help.

tjwalker

Read the article in this link and you'll be ready to attack your crank sensor replacement!

http://www.go.jeep-xj.info/HowtoCPSchange.htm

Micah

Thanks for the link. It really helped with changing the CPS. Unfortunately it still isnt starting.

What now????

DaddyCat

check your fuses in the engine bay:
http://www.lunghd.com/Tech_Articles/...tification.htm

Micah

Already did that.

1988cherokee

have you checked to see if you have power going to the coil?

DaddyCat

Here is a thread that is similar, might make you unhappy if you bought the CPS from autozone but might help get you running:
https://www.cherokeeforum.com/f2/no-spark-coil-76768/