HELP! 4.0 liter engine with 165K - drove her home last week-parked and three days later won't start. Has plenty of fuel. Tuns over perfectly (new battery less than 3 months) but seems like there's no spark. I believe I need new coils. Anyone agree? Easy fix / replacement in my driveway with typical tools? I'll change spark plugs while I am at it. Any suggestions or recommendations much appreciated. TIA Stew

 

First make sure your getting fuel and spark also check to see if it's throwing any codes. I wouldn't assume it's the coil packs thats just throwing parts at it and hoping for a fix,IMO. I'd lean more towards fuel pump or CPS.

 

I appreciate the suggestion. I have to admit this car has never had the plugs or coils changed in 100,000 + miles. The car drove fine from Philly to my place in the Poconos (2 hrs) and I parked it - ran fine - then three days later she won't start. Can a fuel pump simply fail just like that? Would thye pump be an easier repair / replacement? I would love to check for a spark, but I can't find a plug / wire to test! I plead ignorance when it comes to this motor. i DO MY OWN BRAKES AND SHOX, BUT THIS HAS ME STUMPED. I was guessing coils / plugs due to the hi miles and never having changed them ever. Codes .... thatb is something I never considered. If I buy a code reader (is that availoable?) I assume it could pinpoint my problem? Thanks again. BTW - where in PA are you?

 

To read codes >->http://www.wjjeeps.com/faultcodes.htm#ERASE

Code info->.http://www.wjjeeps.com/faultcodes.htm

 

check your codes via the link ol'blue gave you. Yes the pump can fail that quickly and wj pumps have a propensity for problems. You can turn the key to the "on" position for a few seconds then try to start it,if it starts it's probably this http://wjjeeps.com/tsb/tsb_wj_1400201.pdf. The pump is NOT an easier fix than the coils/plugs i'm just saying try to find the actual problem first,could be a sensor issue as well. The plugs are underneath the coil rail,pass. side below the valve cover,take the four bolts out and unplug the connector at the way back and lift off the rail,there are no wires hence the coil-on-plug.It's very simple. Is it cranking fast? I'm near the bloomsburg area,you?

 

Great info guys - thanks a ton. I live in White Haven PA - about a 1/2 hr from Bloomsburg. Stew

 

Small world,lol. Keep us posted with your findings.

 

X2, I'm still learning these Jeeps.

 

Ok - got a code - Thx Blue! - P0320. Per the codes list that means "no crank reference signal at PCM" where does that leave me and what does that mean?

Thanks again guys - I do appreciate all your help. Stew

 

I could be wrong, but my guess is the CPS is bad.

 

Crank Position Sensor, correct? Easy to change or am I doomed to take the car to a tech?

 

Most likely the crankshaft position sensor or the wiring/harness going to it. It's not too difficult to change,it's on the bellhousing. Other less likely,camshaft position sensor or PCM.

 

I just disconnected my battery in the hope it'll clear the code and allow the car to start so I can get it into the garage. I'll give it 10 minutes. Think it'll work?

 

I doubt it but it can't hurt to try. I think it takes 30 minutes for the computer to reset it's self.

 

If after disconnecting the cables from the battery you touch them together, you will erase the memory.