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1996 Jeep Cherokee cranks but doesn't start

Running fine then suddenly sputtered to a stop and has not started for 2 weeks now. Have spark and fuel delivery to engine. replaced spark plugs and wires, dist. cap, rotor, fuel filter, crank sensor and also drained all gas and added 2 gallons of new gas and even checked compression which is ok. Hope to run diagnostic check tomorrow. Could it be bad computer?? But then there would be no spark right? stumped and desperate to get her running!

Cam sensor runs injector pulses. It’s counter intuitive to be looking at the distributor for the fuel trigger, but there it is. The crank sensor runs the spark.

you say you have fuel delivery. So you tested fuel pressure? or did you take a small screwdriver and open the test port and watch fuel spray out? does that translate into 47 to 51 lbs pressure? Must have proper fuel pressure or it wont run.

Thanks for your advice ptptrspp. I will test fuel pressure with guage today hopefully to see if I have that necessary 47 to 51 lbs pressure. Only did a visual fuel pressure test and watched it spray out where it connects to throttle body area (test port i presume). Also did check each of the 4 fuel injectors (4 cylinder 2.5L engine) and were all delivering a nice even mist spray. I will run fuel pressure test today and let you know what I come back with. Much appreciation and respect for your time and knowledge.

Try spraying some starter fluid into the intake and see if the engine tries to fire then. If that works then look into a problem with the fuel delivery system even though it looks like you are getting some fuel at least. If that trick doesn’t work then I would check ignition timing for a problem.

thanks for that input Cougar. I did actually drain a whole can of starting fluid over that past week (and even poured a little straight gas down throttle body) and funny thing is it would almost start…or kind of start i guess but it was still sputtering and only turned over for a second or so. it did not sound normal and seemed like a good sign but still feel like its still off for some reason. i ended up fuel fouling the plugs and have changed them twice now…this time went with champion. i think we poured a bit too much fuel inside so remover all plugs and turned it over and let her spit out whatever was in there and dry out. changed plugs…still nothing??

thanks for input. i guess wasn’t 100% certain if it was a substandard spark or fuel delivery issue…and still not completely sure. so on the advice of a few different mechanical friends (pro’s and non), I guess I have been addressing both spark and fuel and whatever else we can come up with that is a relatively cheap fix and hoping for a positive outcome. still working on it…

ps. we did also “hotwire” the fuel pump when we drained out about 14 gallons from tank and fuel pump seemed to perform fine. also when i turn the key before starting it does turn on for 2 or 3 seconds. when i changed the fuel filter i could feel pressure on the gas tank side fuel line. i’m hoping that fuel pump is okay…seems to be okay but on your advise i know i must check if i’m getting the 47-51 pounds of pressure which is right on the top of the list. because my list is of what to do next is only to run diagnostic…don’t know what else i can possibly check for…ignition module maybe??

will also look into ignition timing. my buddy helped me check that yesterday. distributor (bottom half was on tight and showed no signs of slippage or movement). i was very careful to replace spark plug wires and distributor cap in exact same place when i replaced them…drew a diagram and double checked everything was in order. we will check it again though, thanks.

Ok, I see. Since the starter fluid trick didn’t work I can only think of two things that may be causing this trouble. My first choice is there is too much fuel getting to engine cylinders. The fuel pressure regulator may be defective. If there is an easy way to electrically disable the injectors you could then see if the engine will fire up using starter fluid. If that isn’t the trouble then I would have to say the ignition timing is off for some reason. In the old days you move the disty to see if that was the case. It’s not so easy nowadays. But maybe you still have a disty in your model.

that’s a good idea…nobody i’ve spoken with has come up with that one but it seems like a very logical solution. thank very much for your time and knowledge cougar. i am gonna show my buddy what you’ve wrote here and he can hopefully help disable the injectors and we’ll try to fire her up with starting fluid! …and if not that then we will carry on with digging deeper into the ignition timing setting. aloha~

Well after reading your last relpy it looks like you do have a conventional disty. To see if there is a timing issue mark the current position of the disty as a reference to go back to and then loosen the bolt so you can move the disty. Then while someone is cranking the engine see if you can get the engine started by moving the disty slightly in either direction. If that trick works then you have a timing issue.

all righty, got it! man i was really at a loss yesterday and all we could think of was to hope the diagnostic came back with something useful…or…dare i say it…last resort…tow it to the DEALER. Thanks to you we have a couple more things to check and a new found optimism. will let ya know…cheers.

don’t mean to jump the gun but just out of curiosity…what sort of cost approximately may be involved for parts and labor time for a fuel pressure regulator or the other issue of possible timing issue. I replaced timing chain about 6 years ago when i first bought this truck to the tune of about $1000…hoping that is all in tact still. have 151,000 miles on it.

I think you will be able to get it running by moving the disty. It sounds more like a timing issue now to me. If those things don’t help then let us know and someone here should be able to help you find the solution to the trouble.

I’m not sure about the cost of parts or labor. Parts may run you about 200 dollars depending on the trouble but I’m not sure.

You got it Cougar! Aloha~

THE PROBLEM TURNED OUT TO BE THE IGNITION COIL. REPLACED IT AND SHE STARTED RIGHT UP AND HAS BEEN RUNNING SOLID EVER SINCE!