JEEPIN'around91

i have a 1991 cherokee laredo, last night driving around it ran fine, this morning go out start it up and runs fine, but my volts gauge read low, so i shut it off, and tried to restart it and it wouldnt start. so i figured it was the battery, took it to the parts store and had it checked and it was at 95%. so it wasnt that, came home about 10hrs later after work put the battery back in and it hesitated to start but started. few minutes later i shut it off and tried to restart and it wouldnt start agian. i checked the fuel pressure it was good, checked for spark it sparked, it has a new bosch alternator, new fuel pump, new cap, rotor, plugs and wires, and it cranks fine. i'm thinking weak coil? or crankshaft position sensor.any help?
1991 jeep laredo 4x4 4.0 h.o. auto

TrekkerJmm

I would say the CPS. I don't have the link but in this forum there is a few posts about checking one out with a voltmeter...Tj

JEEPIN'around91

Cranckshaft Position Sensor Testing
test #1)checking across B and c terminals switch your voltmeter to read 0-500 ohms and it should read 150-275 ohms with the vehicle off.
test #2)checking across terminals b and c switch your voltmeter to read 0-5 volts ac, have a partner crank the engine over while testing. should read between .5 and .8 volts

fantic238

Does the engine crank or it doesn't do anything at all?

BlueXJ

If the test of the CPS comes up OK then try just unplugging and re-plugging it a few times to clean the plug contacts.

ZachsXJ

If the CPS and everything checks out you may have a bad starter solenoid. I had that happen to me, where I'd get one click trying to start it and nothing but a HUGE amperage draw on the battery. It takes about 10 minutes to get a starter out and it couldn't hurt to take it to autozone or advanced and get it checked for free.

JEEPIN'around91

i replaced the cps and that seems to have fixed it. thanks guys for all your info