tempest411
NAXJA Forum User
- Location
- Discovery Bay, CA
Hello,
I've owned my '88 XJ for over 20 years now, and except for some CSS issues when I got it, it's run very reliably. Those CSS issues were solved with the Chrysler issued kit that included a new sensor and harness that patches directly into the ECU connector. Last spring I was driving down a road and it just died on me. I was able to restart it right away and drove the rest of the way home without incident. At first I tried to dismiss it as a freak anomoly, but then it did it again a week later to my wife...and then again to myself. I immediately suspected that the CSS sensor was just old and was now failing. It'd been in there since 2000. I did some research and found Cruiser54s write-up about the required output voltage needing to be about .5V. I measured mine, multimeter set to AC, at about .25V (250mV). I changed the sensor with another new one I 'had around' from so long ago, and it also had a measured output of .25V. The Jeep drove ok for a day or so, but then resumed it's stalling behavior. At this point I started thinking about the ECU, the C101 connector, and other possibilities. Over the summer I've cleaned the grounds at the dipstick tube and at the DS fender, replaced the C101 connector with a pair of sealed Deutsch-tech connectors, swapped the CSS sensor AGAIN with a known new factory Chrysler part, replaced the fuel pump, and swapped ECUs (Cardone unit). The symptom has only gotten worse! The last few times I drove it, besides the stalling, I had a great deal of trouble starting it. I could hear it fire a little bit at first, then it would just spin with the starter. Wait a little bit (five minutes), and it will start up and drive as if nothing was ever wrong. And, btw, the CSS voltage output is still about .25V, which leaves me wondering if my meter(Fluke) is measuring it differently than Cruiser54's (peak-to-peak, or not...). What ever's going on is very intermittent, and has an on/off behavior to it. I have replaced the ignition module...got one from O'Relly's, but made in USA...but have not attempted to drive it anywhere. I'm not real confident that the ICM would be it as I've read they almost never go bad, though the description fits. Could something have happened to my flywheel over time that has effected the way it interacts with the CSS? I have read about drilling out the mounting holes to get it closer to the flywheel, but I'm hesitant to do that without be able to take accurate measurements. That would not be easy. There's just barely enough room to install the damn thing! They could've put it at the front of the motor...Hmm..The only bright side to this is that it's now failing often enough that I can bring some stuff with me and reliably test different things on the spot.
Any thoughts on this? I appreciate your suggestions!
Rick
I've owned my '88 XJ for over 20 years now, and except for some CSS issues when I got it, it's run very reliably. Those CSS issues were solved with the Chrysler issued kit that included a new sensor and harness that patches directly into the ECU connector. Last spring I was driving down a road and it just died on me. I was able to restart it right away and drove the rest of the way home without incident. At first I tried to dismiss it as a freak anomoly, but then it did it again a week later to my wife...and then again to myself. I immediately suspected that the CSS sensor was just old and was now failing. It'd been in there since 2000. I did some research and found Cruiser54s write-up about the required output voltage needing to be about .5V. I measured mine, multimeter set to AC, at about .25V (250mV). I changed the sensor with another new one I 'had around' from so long ago, and it also had a measured output of .25V. The Jeep drove ok for a day or so, but then resumed it's stalling behavior. At this point I started thinking about the ECU, the C101 connector, and other possibilities. Over the summer I've cleaned the grounds at the dipstick tube and at the DS fender, replaced the C101 connector with a pair of sealed Deutsch-tech connectors, swapped the CSS sensor AGAIN with a known new factory Chrysler part, replaced the fuel pump, and swapped ECUs (Cardone unit). The symptom has only gotten worse! The last few times I drove it, besides the stalling, I had a great deal of trouble starting it. I could hear it fire a little bit at first, then it would just spin with the starter. Wait a little bit (five minutes), and it will start up and drive as if nothing was ever wrong. And, btw, the CSS voltage output is still about .25V, which leaves me wondering if my meter(Fluke) is measuring it differently than Cruiser54's (peak-to-peak, or not...). What ever's going on is very intermittent, and has an on/off behavior to it. I have replaced the ignition module...got one from O'Relly's, but made in USA...but have not attempted to drive it anywhere. I'm not real confident that the ICM would be it as I've read they almost never go bad, though the description fits. Could something have happened to my flywheel over time that has effected the way it interacts with the CSS? I have read about drilling out the mounting holes to get it closer to the flywheel, but I'm hesitant to do that without be able to take accurate measurements. That would not be easy. There's just barely enough room to install the damn thing! They could've put it at the front of the motor...Hmm..The only bright side to this is that it's now failing often enough that I can bring some stuff with me and reliably test different things on the spot.
Any thoughts on this? I appreciate your suggestions!
Rick