So, the alternator is turning and the battery has plenty of juice, but it just won't catch. It just keeps trying and trying to no avail. It's of course twenty years old and I've been noticing alot of blow-by coming out, so I'm worried it's dead for good this time unless I rebuild. Please tell me I'm wrong.

 

What have you done to diagnose?

Do you have fuel? Are you getting spark?

You haven't given anyone much to work with other than the battery and alt are good.

 

FUEL
/ \
/ \
/ \
AIR ------ FIRE

Triangle of life

 

Yea my 90 cherokee isn't cranking on its on now either. I checked fuel pressure and spark. Both are good. My problem is no injector pulse when the key is in the start position. I can spray a little starting fluid in and it fires right up. I stated on a previous thread that it was the crank sensor but it turns out my mechanic was wrong....again. I'll let you know what I find on mine. Maybe it'll be some help with yours.

 

Pull a spark plug, ground the threads, see if there is a nice blue/white spark. If nothing, you have no spark. If you have bright blue spark, it could be fuel or timing.

Next...

Open the intake, crack the throttle plate open and squirt starting fluid inside. Try and start. If it starts, you aren't getting fuel.

It could be the Crank position sensor as they are common. Or it could be the cam position sensor located right by the distributor.


Could be cam position sensor.

 

Great! I'll have him check that next. Thanks