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my 91 heep wagoner 4L won't start!

zebulon

NAXJA Forum User
Location
alabama
I have 91 jeep wagoner 4L. It started out as excessive case presure from blowby. I replace the rings, piston, valve seals, head gasket,fuel pressure regulater,water pump, plugs, wires, rotor, cap, and all of the emission controll hoses. It ran when I parked it now it dosn't want to start. It is getting fuel, spark, and it defenditly has compression. The only thing i can come up with is timming. This has baffled my brain. Can anyone help? thank you for your time.

the bad thing is i'm almost done at nashville auto-diesel college, where i'm learning to be a mechanic
 
It means the CPS is shorted out. Before you replace it, check the wiring going to it. The insulation can break down due to old age and from exposure to radiant heat from the exhaust manifold. It can even melt if it touches the manifold.
 
thanx i'll check it the wires and do those wires to the cps have voltage or recieve it? how does it work? thank you
 
The CPS generates a small AC voltage. If it reads 0 ohms, you have a problem. Like the doctor said, disconnect it from the harness and measure it. I had the cable get over next to the exhaust manifold and it melted. The thing that does not make sense is that you say you have spark. If the CPS is really reading 0 ohms, you will not get spark.

Since you had the motor apart, there is a good possibility that you got the distributor back in 180 degrees out of phase. That will give you spark, just not at the right time. Also on a gas engine, especially the 4.0L, a non start situation can lead to the plugs getting soaked with gas. In that case they don't fire well if at all. Pull the plugs and make sure they are not wet. If they are, clean them with carb cleaner, let them dry and then replace them.
 
I FEEL LIKE A DA. The ohm meter was set on 2M. now that wouldn't work now would it. thanks again. i'm trying the timeing today.
 
Re:still my 91 heep wagoner 4L won't start!

the damn thing still won't start. the CPS is good, I think i have it in time, still no start. the starter turns but then the battery dies.
 
it still dosn't start. It it time, cps is good, and has fuel pressure. the only symtom is that the starter turns but drain battery.
 
it still dosn't start. the cps is good, in time, and has fuel pressure. the only symtom is starter turns but drain the battery.
 
in my first xj i had the problem of teh starter doing the same thing i could charge it all night and then go to start it and it would drain the battery in just a few cranks as it turned out i had a bad started that had shorted out internally and had also fryed the solinoid as well. maybe that will help i hope. if not i dunno sorry.

Trent
 
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