Jeep Repair Problems? Ask a Mechanic for Answers ASAP
When you are looking at the side of the engine where the distributor is, the ignition coil is located to the right of the distributor, bolted to the engine block. You can follow the ignition cable from the distributor cap to the coil.
The most common no-start problems on Grand Cherokee are the fuel pump and the crankshaft position sensor.
Does the engine start at all? Did it run before you began replacing parts?
OK...let's do some diagnosis...
Turn the key on, and see if the volt gauge and the fuel gauge on the dash are working normally.
Let me know.
Another thing I would like you to check:
Your Jeep should have (2) oxygen sensors.
Inspect the rear oxygen sensor (after the catalytic converter) and make sure the wiring is not rubbing on the rear driveshaft.
OK, are you able to check for spark without getting zapped?
I would check for spark on the ignition cable coming from the coil to the distributor.
Let me know if you are not sure how to do this.
Stick a screwdriver in the end of coil wire, and position the screwdriver in such a way that there is a small gap (1/4 inch or so) between the screwdriver metal and the metal of the engine block.
The other end of the wire should still be attached to the ignition coil, of course. This is a better test, because the engine block is a good ground.
Crank the engine over and check for spark.
OK...I need to get off the computer pretty soon here...would you like to continue this in the morning?
I will give you a few more things to check:
Use a test light to check for power to the ignition coil while cranking. Unplug the 2-wire connector to check.
The other wire should have blinking ground while cranking.
It is possible the ignition coil is faulty...it's kind of rare, but it is possible.
Another possibility is the crank sensor you installed is faulty, or it is not adjusted correctly.
Look at the old crank sensor...the hole where the bolt goes through...is the hole circular, or elongated?
The hole on the sensor is a circle. Old one and the new one is exact. I also think it could be the coil but do you think the fuel pump is bad?
That tells me the crank sensor is the non-adjustable type, so it is probably OK.
The easy way to check for bad fuel pump: spray some carb spray or intake cleaner spray into the throttle body and crank the engine. If it starts, or tries to start, then you have a lack of fuel, which usually means the fuel pump is faulty.
I am concerned about the lack of spark.
The best test is to connect a fuel pressure gauge to the fuel rail.
You are welcome!
I will check back in the morning.
Any luck so far? I was thinking about your problem this morning. Another possibility is the engine computer is not controlling the igniton coil properly.
This is a common problem, but it is usually intermittent...normally does not cause a true no-start.
I would like to know the fault code that AutoZone retrieved.
Glad to hear that you got it running.
I'll be around if you have questions in the future.
Thanks for letting me know.
Please click 'accept' so I can get credit for my answers.