i was driving down the road yesterday and my 96 jeep cherokee cut off. and it would not start again. it will turn over but not start. i pour gas in the throttle and still no spark. i replace the ignition coil and still no spark. what could it be. please help.

 

CPS.

 

Pouring gas would not make spark

 

no but its a way to test if it was the fuel pump or not. but it just isnt gettin spark.

 

probably the crank case position sensor. think it works on ohms so you can check it.

 

what is the best way to check it. i thought maybe it would be the distributor pickup but sounds hard to change just to check.

 

99.9% positive it's the crank sensor. Had this problem on mine and drove me nuts. VERY common issue with jeep cherokees. Good news it's it's only like a $50 sensor. Semi-bad news is it's a PITA to get to. Luckily someone figured this one out:

http://greatlakesxj.activeboard.com/...picID=24211453

 

thx man. it does sound like tht is it. i hope i can find some extensions. will b tryin to change it 2morrow.

 

do i need all those extensions to get to it

 

absolutly

told you it's a PITA

 

ok i change the crankshaft sensor and it did not help. i check to make sure there is power running to it and there was. i also check to make sure power was running to the nss and there was. but when i check to see if power is running to the coil there isnt no power.

 

Do you have any codes?

Replacing parts without checking for codes is pointless. Any time someone can't start a vehicle someone pops up and is dead certain it's a crank sensor, and most of the time it's NOT the crank sensor.

Don't buy ANYTHING until you check the codes. I've been on many threads recently where someone can't start their vehicle that has shut off, and it usually sounds like it's a fuel pump.

Look at my profile and follow threads with "No Start" symptoms. I've assisted many others. Find the one that suits you most and follow it.

The most important thing is codes. If you didn't have P1391 then you had no reason to replace your crank sensor. Check codes regardless of the check engine light. Just because it hasn't illuminated doesn't mean the PCM hasn't registered any. It waits for a set amount of failures on somethings. Things that die outright might not have set off the light.

Also, did you check your fuses? That's the first thing you should check. Check the relays too. To test them swap them and see if they still perform their function (they're all the same). I swap everything with the "Starter" simply because it's the easiest to tell if it's working or not. If it tries to start it's fine. If it doesn't, it's a dud and it needs to be replaced. If after you replace it it dies again then you have another electrical problem to troubleshoot, in that particular relay circuit.

 

well iv been replacing stuff and then returning if it didnt fix the problem.

 

If you can do that then just borrow a code scanner from the place you're getting parts. Save you many trips and time. Then you can use the extra money that would have been spent on gas to spend on beer while you reduce you inhibitions enough to not care about the time and effort you'll spend on fixing the problem.

And then forget to do something in the reassembly process and start all over next week when it dies again.

 

A bad CKPS does not always throw a code coffeecommando. When mine went bad there was no codes. When a jeep cuts out while driving suddenly, it's almost always the CPS whether you want to believe it or not.

He verified spark is the issue, not fuel, so the pump is fine.
He can crank the engine so the ignition switch is fine.
He changed the coil so that (most likely) rules that out.

OP did you inspect the wiring running to the crank sensor while you were there? I've seen cases where the wires touched the exhaust manifold and shorted out. Any damage to these wires could result in a bad sensor signal, so make sure they look good and the insulation is intact. Also I would check for continuity between the CPS connector and the other end of the wire to be sure.

Also check for codes to make commando happy.

Another thing to check now would be your grounding points. One is beside the battery attached to the passenger side fender. The other is on the back of the valve cover attached to the firewall (drivers side). In each case inspect the wire/strap for corrosion, and clean/sand the contact points till nice and shiny and reattach. Also check the oil filler tube brace connection, as some sensors have grounding points that attach there.

Report back.