yamifj1200

Hello folks, New to the group here.
I am having a problem with my 1997 jeep grand cherokee with a 4.0 liter engine. The jeep has 197.000 miles and had been running fine.

Yesterday while driving home from work at a steady 65 mph the engine shut down. No miss fires, no stumble it just shut off. I drifted to the shoulder of the road and tried to restart the engine. All the electronics gauges, stereo and interior lights worked fine. The engine cranked over just fine, strong battery but would not start. No check engine light was on. After a 15 minute wait I was able to the start the engine again.

Once home I checked the easy items, battery connections, wiring connections in the engine compartment, fuses and I noticed there was a relay for the fuel pump. I swapped out that relay with the one for the starter. I was able to restart the engine and run it for 30 minutes with out an issue.

Today I drove it to the parts store today to replace the relay I thought was bad and I was unable to start the engine again. I don't have a check engine light and my cheap odb II found no codes.

I hate taking it to the dealer, but at this point I dont know what direction to turn. It could very well be the fuel pump, but the fuel rail on the motor was full of fuel and under pressure. It could be the crank sensor but I have no way to check it.

I look forward to hearing what the experts here think.

I appreciate the help..

Eric M

72gremlinkid

Hello,
It sounds like you need a new camshaft position sensor. It is a sensor inside the distributor. If you research that on the forum here you will see lots of problems of it shutting off randomly then being able to restart it due to this sensor being bad. It is a common problem with these jeeps. Throw a new sensor in and get to 200k!

yamifj1200

Great thanks for the quick reply. Thats good news.


Eric M

yamifj1200

I installed a brand new cam position sensor and it does just what it did before. Oh well on to the next part of the ignition.

On my Cen-Tech ODBII I now get a code of P0320 according to the cen tech manual it descibes this code as an 'Ignition/Dist Engine Speed Input Circuit Malfuntion"

I am at a loss and will be towing it to the dealer.. I hate to but I need my jeep running again..

Eric M

tiwvr1

Crank sensor, another very common problem. Even if it isnt bad, replace it with a acual jeep part, not aftermarket

asoto

had same problem for days. buy a can of carburetor cleaner remove filter cover and spray clean inside and around the butterfly to remove gumk, wipe all gook off and restart engine while running spray more cleaner inside. this should help you, it helped me. reply to asoto

asoto

asoto left you a suggestion. please read may help you.

4Doors

Does asoto always refer to himself in 3rd person? Does he perhaps have another login name that he uses to give himself virtual props but he forgot which name he was logged in under?

4Doors recommends that you consider your fuel pump. He thinks it would be wise to check your pressure. He knows that sometimes when they get hot they will shut off, but after they cool down a bit they will work just fine.

jeeptech40

when the vehicle wont start have u noticed if the voltage gauge or fuel gauges r flat/inop if so with the key on go to the passengers side of the engine compartment near the rear of the block is the connector for the crank sensor dissconnect and check gauges again if they return to normal with sensor dissconnected then the crank sensor is shorted and pulling down the 5volt ref circuts replace and should be fine

yamifj1200

Thanks to all who responded to my questions. It turned out to be the crankshaft sensor. Its been replaced and Im happy to be driving my old jeep again. Thanks again to all who helped. Great group here..
Thanks again..

Eric M

bryanbluett

Hi, I have a problem, My jeep would not start and i found that the battery terminals were corroded, so I cleaned the wires and replaced the battery clamps. The jeep started up with no problems but then the gauge panel stopped working. the only thing that works on it is the lights, and symbols. I removed gauge panel-no blown tracings, checked all fuzes-good, missing air bag model from under the drivers seat though, have checked relays and can not find the problem.... Help!

francisco.tanner

Hey, it might be your computer because this happen to me too when i was driving my jeep has shut down on me too and put into it every part that would of cause that problem and then i changed the computer and its working great now.

dave1123

Hey Francisco, you just responded to a 6 year old post! Nice try anyway.

Random shutting off for no reason, then restarting after a short wait is a classic symptom of a failing crank sensor. Unless it dies completely, it usually won't set a trouble code. I'm not saying your computer wasn't bad, but I'm saying it's an expensive part to replace as a first step.

Crank sensors are a magnetic switch and after many years they lose their strength. Loss of a strong signal tells the computer to shut down the engine. I'd rather try a $50 part then replace a $200+ rebuilt part that may or may not be the problem.

I got lucky with my jeep. The original crank sensor lasted 15 years and 195K miles before it died. My advise is to buy only Mopar sensors for replacement because of the quality of construction they are produced with.

Welcome to the Forum! It sounds like you used the "Parts Cannon!" LOL!

dave1123

Delete! I answered a 6 year old post also! Bryanbluett

97grand4.0

got me also.