88 Laredo Dies When Hot
Saudade
06-02-2004, 03:44 PM
My 88 Laredo would die when hot and stay dead until it cooled off. When it shut down it was like I turned the key off. No warning, just shutdown. Took about 20 minutes to cool off and then it would start again, run until it got hot again and then die.
The temp was pretty normal and it ran fine until it quit. Based on comments in here and a few other websites, I traced the source of the problem to the Crankshaft Position Sensor.
Special thanks to http://autorepair.about.com/library/faqs/bl077g.htm for the wiring diagram and test procedure.
A quick trip to my local Jeep dealer and $50 later, I'm back in business.
The temp was pretty normal and it ran fine until it quit. Based on comments in here and a few other websites, I traced the source of the problem to the Crankshaft Position Sensor.
Special thanks to http://autorepair.about.com/library/faqs/bl077g.htm for the wiring diagram and test procedure.
A quick trip to my local Jeep dealer and $50 later, I'm back in business.
AZFlyingDiver
06-02-2004, 06:33 PM
Good of you to pass that along...
How did you trace it back to the CPS - error code?
How did you trace it back to the CPS - error code?
Saudade
06-03-2004, 12:39 PM
Good of you to pass that along...
How did you trace it back to the CPS - error code?
No, I never got any error codes. After some basic troubleshooting, I concluded that it was electrical (ignition) in nature. I validated it with my timing light. Once it was hot, I cranked and got no light. Once it cooled off, the light began flashing again. I then tested the coil, replaced the cap and rotor and checked some other wiring. At that point, I started searching Google and found numerous hits. I was able to eliminate the fuel, cat converter, and non "spark" related hits. Using the remaining hits, I refined my search criteria until I seemed to retrieve more CPS related hits that anything else.
The link I posted had the test for the CPS. It was the "silver bullet" I needed. For laughs, after I replaced the CPS, I took the old one, hooked up my ohm meter and then placed in into a pot of boiling water. Once it heated up, it opened the circuit. I then plunged it into a pot of cold water, and after about 30 seconds, I got continuity again. It now rests in my trash can.
How did you trace it back to the CPS - error code?
No, I never got any error codes. After some basic troubleshooting, I concluded that it was electrical (ignition) in nature. I validated it with my timing light. Once it was hot, I cranked and got no light. Once it cooled off, the light began flashing again. I then tested the coil, replaced the cap and rotor and checked some other wiring. At that point, I started searching Google and found numerous hits. I was able to eliminate the fuel, cat converter, and non "spark" related hits. Using the remaining hits, I refined my search criteria until I seemed to retrieve more CPS related hits that anything else.
The link I posted had the test for the CPS. It was the "silver bullet" I needed. For laughs, after I replaced the CPS, I took the old one, hooked up my ohm meter and then placed in into a pot of boiling water. Once it heated up, it opened the circuit. I then plunged it into a pot of cold water, and after about 30 seconds, I got continuity again. It now rests in my trash can.
AZFlyingDiver
06-03-2004, 12:52 PM
Ahhh...good piece of invesitgative work...
(And now I know why my girlrfriend's circuit opens up when her CPS gets heated up! lol)
Seriously, thanks for passing along -
(And now I know why my girlrfriend's circuit opens up when her CPS gets heated up! lol)
Seriously, thanks for passing along -
Automotive Network, Inc., Copyright ©2026