Brody
October 25th, 2008, 07:44 PM
I have had a starting issue with LaDawn's Jeep Cherokee for awhile and have been trying to diagnose it. I chased all sorts of threads and posts on the internet, literally reading hundreds of threads on many forums. Seems like the basic 'engine turns over, no fuel/spark/no start' is a rather universal problem that even dealerships can't sort out.
Turns out that there are two recurring fixes, neither of which is found in dealer information, Chilton's or Haynes. Here they are:
There are two screws that hold the cover plate on to your PCM/ ECU. This is located behind the coolant overflow on the passenger side of the rig. Jeep made these screws too long by about 1/4" and they tend to short out the circuit, sometimes intermittently. Remove the overflow. Pull the connectors off. Take a Torx screwdriver and back the screws out 1/4". If this fixes the problem, replace with shorter screws or grind 1/4" off old ones.
The second fix came about after reading two sentences in one of the threads. " To check to see if your Crank Positioning Sensor is good, unplug the plug from the passenger side of the motor that goes to your sensor (located on the driver's side of the bell housing above the shift linkage bracket on an automatic). Turn on your key and if your guages now work, the sensor is bad." This was the problem for me. Nowhere else did this information appear and the dealers couldn't tell me this simple trouble shooting hint.
Here is the link to the site that had the most information for chasing down the same problem. Turns out there are about 40 things that cause similiar problems for XJs, no matter the year model.
http://forums.cnet.com/5208-6305_102-0.html?forumID=78&threadID=248386&start=0&tag-w;forums06
That doesn't work, go to : Jeep Grand Cherokee stalling fixed! on CNET Car Tech Forums page 3 of 5 or post #145of 290
Hopefully this will save someone the headaches, not to mention the cost of a new fuel pump. I ran a hot line directly to mine and it wouldn't work, so made the logical assumption that the pump was bad. Turns out that if the sensor is shot, your pump isn't getting the right signal, hot line or not.
Want to buy an 1998 XJ with a new fuel pump and Crank Sensor? Its going to be for sale. Good shape, too. Call LaDawn.
Turns out that there are two recurring fixes, neither of which is found in dealer information, Chilton's or Haynes. Here they are:
There are two screws that hold the cover plate on to your PCM/ ECU. This is located behind the coolant overflow on the passenger side of the rig. Jeep made these screws too long by about 1/4" and they tend to short out the circuit, sometimes intermittently. Remove the overflow. Pull the connectors off. Take a Torx screwdriver and back the screws out 1/4". If this fixes the problem, replace with shorter screws or grind 1/4" off old ones.
The second fix came about after reading two sentences in one of the threads. " To check to see if your Crank Positioning Sensor is good, unplug the plug from the passenger side of the motor that goes to your sensor (located on the driver's side of the bell housing above the shift linkage bracket on an automatic). Turn on your key and if your guages now work, the sensor is bad." This was the problem for me. Nowhere else did this information appear and the dealers couldn't tell me this simple trouble shooting hint.
Here is the link to the site that had the most information for chasing down the same problem. Turns out there are about 40 things that cause similiar problems for XJs, no matter the year model.
http://forums.cnet.com/5208-6305_102-0.html?forumID=78&threadID=248386&start=0&tag-w;forums06
That doesn't work, go to : Jeep Grand Cherokee stalling fixed! on CNET Car Tech Forums page 3 of 5 or post #145of 290
Hopefully this will save someone the headaches, not to mention the cost of a new fuel pump. I ran a hot line directly to mine and it wouldn't work, so made the logical assumption that the pump was bad. Turns out that if the sensor is shot, your pump isn't getting the right signal, hot line or not.
Want to buy an 1998 XJ with a new fuel pump and Crank Sensor? Its going to be for sale. Good shape, too. Call LaDawn.