So 1993 Jeep Cherokee 4.0 HO. Auto.
I trust you guys more than Jeepforum...
The fuel pump makes sound and brings fuel pressure up, The starter motor tturns and turns the engine. the battery has 12.6 volts and 650 CCA according to the test device that Napa loaned me.
So, it seems that spark is not making it to the plugs. Cap and rotor are in good shape. thinking it is Fuse or Relay (is there a relay for the fuel system?) or ECU, could it be the ECU?
What says you good people?
thanks,
Eric M
Im no expert on the 4.0 but the crankshaft position sensor is notorious for going on out on these things. IIRC this was one of the symptoms.
Yep, crank sensor.
I know nothing about Jeeps, but my RX-7 had a fuse that controlled such things like spark (people pulled them to de-flood the engine). It's probably an easy enough check that it's worth looking at.
Crank sensor.
That's how mine acted.
Shawn
Sometimes you can unplug and reconnect the crank sensor and they will start. It's not a fix, but if it works, it will pretty much confirm the sensor is your problem. They are a pain in the butt to change out, but not the worst job ever. Have a u-joint and about 3 feet of ratchet extensions handy (really).
OK cool everyone, I will check the Crank Sensor in the morning.
You can check a/c voltage coming out of it if you have a meter.
Forgot which pins to do (theres 3) but process of elimination might help 
I found this (written on June 4th) on "another" forum.
The most likely cause of it cranks and cranks but won't start up is the Crankshaft Position Sensor (CPS) located on the transmission bell housing. Often this part is also referred to as the CranKshaft Position Sensor (CKP) CPS/CKP failure is very common. The CPS/CKP can stop working with no warning or symptoms and the engine will not run or the engine may randomly stall for no apparent reason.
Crank Position Sensors can have intermittent “thermal failure”. This means that the CPS/CKP fails when engine gets hot, but works again (and will test as “good”) when it cools back down.
Begin with basic trouble shooting of the start and charge systems. Remove, clean, and firmly reconnect all the wires and cables to the battery, starter, and alternator. Look for corroded or damaged cables or connectors and replace as needed. Do the same for the grounding wires from the starter to engine block, and from the battery and engine to the Jeep's frame/body. Jeeps do not tolerate low voltage or poor grounds and the ECM/ECU may behave oddly until you remedy this.
Symptoms – - Starter cranks and cranks but engine won't start up and run. - Fuel gauge and voltage gauge may not work or display properly. - You sometimes will have No Bus on the odometer after 30-60 seconds. - A failed CPS/CKP may or may not throw a CEL trouble code. - No spark at the spark plugs. - Fuel pump should run and prime for 3-5 seconds.
If the CPS/CKP is failed sometimes the OBD-II trouble code reader cannot make a connection to the ECU/computer or cannot read Check Engine Light/MIL codes because the CPS/CKP has failed. Disconnect the code reader, disconnect the CPS/CKP wire connector, and reconnect the code reader. If the code reader establishes contact with the ECU and scans, your CPS/CKP is failed and needs to be replaced.
Diagnostic steps to confirm the CPS is the cause of your no-start
You should be able to verify a bad cps, by unplugging it, and turning the ignition key to on. If the voltage gauge and/or the fuel gauge now displays correctly, replace the CPS.
Unplugging and reconnecting the CPS sensor where it connect to the main harness near the back of the intake manifold usually resets the ECU and if the jeep fires right up after doing this you can bet that the CPS is faulty and needs to be replaced.
Exchange the fuel pump relay and the ASD relay with one of the other similar ones in the PDC to eliminate the relays as the cause of the no-start. Confirm that the fuel pump to runs for 3-5 seconds when you turn the ignition key to ON.
Eliminate the NSS as a cause of no start. Wiggle the shift lever at the same time you try to start. Put the transmission in Neutral and do the same. Do the reverse lights come on when the shifter is in Reverse?
Inspect the wires and wire connectors at the O2 sensors on the exhausts pipe. A short circuit from melted insulation or from broken O2 sensor wires can blow a fuse and the ECU/ECM will loose communication. Don’t get tunnel vision and assume the sensor is bad (unless it tests bad with a meter). Damaged wiring or a dirty connector can inhibit the signal from making it to the computer. Inspect/test/clean/repair wiring or connectors as necessary.
CPS Testing
Crankshaft Position Sensor Connector (CPS/CKP)
TESTING PROCEDURE 1991 – 2001 4.0L H.O. engines
TESTING PROCECURE for 1987 – 1990 4.0 L engines
Test # 1 - Get a volt/ohm meter and set it to read 0 - 500 ohms. Unplug the CPS and measure across the CPS connector's A & B leads. Your meter should show a CPS resistance of between 125 – 275 Ohms. . If the CPS is out of that range by much, replace it.
Test # 2 - You'll need a helper for this one. Set the volt/ohm meter to read 0 - 5 AC volts or the closest AC Volts scale your meter has to this range. Measure across the CPS leads for voltage generated as your helper cranks the engine. (The engine can't fire up without the CPS connected but watch for moving parts just the same!) The meter should show .5 - .8 VAC when cranking. (That's between 1/2 and 1 volt AC.) If it's below .5vac, replace it.
The 2000 and 2001 will have the CPS in the same location on the bell housing, but the wire connector may be on the passenger side, not as shown in the diagram below. Simply follow the wire from the sensor to the connector.
Source: http://www.jeepforum.com/forum/f11/96-cherokee-wont-start-1045172/
Oh, I found that post AFTER I had gotten the advice here. But it did go into good detail.
Damn.
I can see the bolt. I can touch the bolts (just barely) But I can not for the life of me no matter how many extensions I use, or wobbly extensions I use, can I get a socket head on them.
I am out of swear words, I am giving up for tonight. tomorrow I will jack it up (on jack stands) and attack it from the bottom.
who the hell decided for it to go on the back side of the bell housing anyway? jerk automotive engineers, that's who.
I have had success pulling bell-housing bolts with 2 - 24" extensions and a universal or two. That puts your ratchet back by the front u-joint where you can actually put some oomph behind it. Never tried it on a Jeep before so that might not help any.
Learning to swear in Farsi might help too.
Good luck!!
heheh.. its only hard the first time.
Do you have flex head ratchet wrenches?
Vigo wrote: heheh.. its only hard the first time.
yes, but it got dark and I was frustrated, hadn't tried tried that one yet.
I have a spare next to my desk at work.
Ours did it and changed Coil Pack and fixed!!!
Try it first!
^ nice charger. 83 1/2 is a rare bird 
Coil packs werent used on the old Cherokees. They had a regular old distributor and wires and one coil.
I think the switchover to the COP arrangement was in '00 or '01.
I got it.
I had to go from underneath with a n 18 inch extension and a wobbly head. It is an 11mm bolt head, just for the record.
It was harder to get out than to put in, taking out took a while, one little click at a time on the ratchet. Putting it back in I was able to get my ogre hands up in there and spin the bolt most of the way with my fingers.
Fired right up.
Thanks for the advice and encouragement !
I love a good success story!
took it to Sonic ( 2 for 1 shakes) it drove smoother than any time I have owned it.
Good to hear it's fixed, and best wishes for your trip.
neon4891 wrote: Good to hear it's fixed, and best wishes for your trip.
Thanks!
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