1990 Cherokee Laredo won’t stay running
#17
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Year: 1990
Model: Cherokee (XJ)
Engine: 4.0
We could just make the video, but I want the money after all the bull**** I went through. We'll keep an eye on this.
#18
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Year: 1989
Model: Comanche (MJ)
Engine: 4.0
If I believe the other thread, apparently an HO will continue running if the cam sensor is unplugged but will not start with it unplugged. In that thread, it was a 2000 that stripped the distributor gear and likely ran without oil pressure until the owner stopped and it wouldn't restart. I think we need someone to test that as well.
#19
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Year: 1989
Model: Comanche (MJ)
Engine: 4.0
If we're getting hung up on what to call it, note the FSM also refers to the crank sensor as the "engine speed sensor". Our resident Renix guru Cruiser54 is correct. The Renix uses the sensor in the distributor to initially figure out which stroke the engine is on because you can't tell that from the crank sensor, so it knows when to fire the injectors and spark. It makes no difference if you unplug it once started. If the sensor is not working, it will "guess" and usually start and run fine anyway.
From the 1988 FSM:
"The sync pulse signal input and engine speed sensor input
allow the ECU to establish the necessary reference point to
synchronize the fuel injection."
From the 1988 FSM:
"The sync pulse signal input and engine speed sensor input
allow the ECU to establish the necessary reference point to
synchronize the fuel injection."
#20
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Year: 1990
Model: Cherokee (XJ)
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And guess what?
A bad sync sensor was NEVER the cause of a driveability issue.
We only happened to find they were bad when scanning the system looking for other things.
Hey, lawsoncl!! Now YOU owe me the $100. You tricked me. LOL.
A bad sync sensor was NEVER the cause of a driveability issue.
We only happened to find they were bad when scanning the system looking for other things.
Hey, lawsoncl!! Now YOU owe me the $100. You tricked me. LOL.
#21
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Year: 1989
Model: Comanche (MJ)
Engine: 4.0
<slowly waves hand> "These are not the sensors you're looking for!
Yeah, Chrysler renamed things when they took over, to camshaft position sensor (cps) and crankshaft position sensor (ckps). I just get annoyed that everyone abbreviates the crank sensor to CPS, when that's really the sensor in the distributor. But even that's confusing when you have a coil rail, because that assembly ain't distributing a spark.
Yeah, Chrysler renamed things when they took over, to camshaft position sensor (cps) and crankshaft position sensor (ckps). I just get annoyed that everyone abbreviates the crank sensor to CPS, when that's really the sensor in the distributor. But even that's confusing when you have a coil rail, because that assembly ain't distributing a spark.
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