Crankshaft position sensor
#17
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Year: 1999
Model: Cherokee
Engine: 4.0
Last edited by Brian Day; 09-18-2017 at 07:00 PM. Reason: Spelling errors
#18
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That has the hallmarks of a major electrical failure. I would start by thoroughly cleaning and inspecting every major connection and ground location under your hood. Not taking any for granted. I would then search the major harness portions for any type of chaffing against metal brackets and such. I would also do a harness shake test in the driveway at idle to see if I could get the engine to cut out while wiggling the harness.
Particularly inspect the main cable from the battery positive to the PDC (fuse box under the hood).
Here is some visual information on the ground locations:
Particularly inspect the main cable from the battery positive to the PDC (fuse box under the hood).
Here is some visual information on the ground locations:
#19
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Year: 1999
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[QUOTE=jordan96xj;3423558]That has the hallmarks of a major electrical failure. I would start by thoroughly cleaning and inspecting every major connection and ground location under your hood. Not taking any for granted. I would then search the major harness portions for any type of chaffing against metal brackets and such. I would also do a harness shake test in the driveway at idle to see if I could get the engine to cut out while wiggling the harness.
Particularly inspect the main cable from the battery positive to the PDC (fuse box under the hood).
Thank very much! That video is extremely helpful I didn't know about a couple of those grounds, I'll definitely pull them off and check them out I seriously hope this is the end of my issues...
Particularly inspect the main cable from the battery positive to the PDC (fuse box under the hood).
Thank very much! That video is extremely helpful I didn't know about a couple of those grounds, I'll definitely pull them off and check them out I seriously hope this is the end of my issues...
#20
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After spending most of the morning meticulously gowing over all the grounds in the previously posted video and double checking all of the plugs I could find. My jeep seems to be running a lot smoother at idle, the throttle response even seems better this may be my imagination though lol however I just drove it on the freeway about 7-8 exits and she was running like a top, I stopped on the off ramp to turn around and head home happy as can be because I figured my issue was gone when it just flat out dies... won't fire for the first 3-4 attempts to restart then on the 5th crank I held it a bit longer and she started to spit and sputter as if it was trying to fire then finally the 6 crank she's alive and running smooth I got it back home with out a hitch. Turn it off and same thing hard to start... could it be the ground cleaning was only one of my issues could a bad ground caused the fuel pump to start to fail (no idea what brand fuel pump is in it, I know it was changed a little over two years ago by the previous owner) I'm leaning toward the fact I may have had more than one issue going on. Any thoughts would be much appreciated.
#21
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Although the driveability symptoms you are observing (transient stalls) could be caused by a failing fuel pump, I don't think that would explain what is going on with the dash cluster. A total dropout of the speedometer and tachometer signals.
Does this -ever- happen at idle in the driveway?
Does this -ever- happen at idle in the driveway?
#22
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Although the driveability symptoms you are observing (transient stalls) could be caused by a failing fuel pump, I don't think that would explain what is going on with the dash cluster. A total dropout of the speedometer and tachometer signals.
Does this -ever- happen at idle in the driveway?
Does this -ever- happen at idle in the driveway?
#23
CF Veteran
The symptoms seem like what would happen if the PCM disconnected the ground from the ASD relay. Which is what it would do if it went without signal from the engine timing sensors for a few seconds. I assume the 99 still has a distributor and rotor/cap. If so, I would either be suspecting that a poor quality CPS was installed the last time around (what brand was it?). Or perhaps the Camshaft Position Sensor (under the distributor cap) is not providing a good signal.
Was the last crankshaft position sensor that went in a Mopar OEM sensor?
You mentioned that it was oem, but there is also a company called "oem" that makes sensors (Original Engine Management is the name). So did you personally get a Chrysler/Mopar sensor and have it installed? Or did someone say that they put in a "oem" sensor?
Maybe a better way to ask the question, is how much did you pay for the sensor?
Was the last crankshaft position sensor that went in a Mopar OEM sensor?
You mentioned that it was oem, but there is also a company called "oem" that makes sensors (Original Engine Management is the name). So did you personally get a Chrysler/Mopar sensor and have it installed? Or did someone say that they put in a "oem" sensor?
Maybe a better way to ask the question, is how much did you pay for the sensor?
#24
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The symptoms seem like what would happen if the PCM disconnected the ground from the ASD relay. Which is what it would do if it went without signal from the engine timing sensors for a few seconds. I assume the 99 still has a distributor and rotor/cap. If so, I would either be suspecting that a poor quality CPS was installed the last time around (what brand was it?). Or perhaps the Camshaft Position Sensor (under the distributor cap) is not providing a good signal.
Was the last crankshaft position sensor that went in a Mopar OEM sensor?
You mentioned that it was oem, but there is also a company called "oem" that makes sensors (Original Engine Management is the name). So did you personally get a Chrysler/Mopar sensor and have it installed? Or did someone say that they put in a "oem" sensor?
Maybe a better way to ask the question, is how much did you pay for the sensor?
Was the last crankshaft position sensor that went in a Mopar OEM sensor?
You mentioned that it was oem, but there is also a company called "oem" that makes sensors (Original Engine Management is the name). So did you personally get a Chrysler/Mopar sensor and have it installed? Or did someone say that they put in a "oem" sensor?
Maybe a better way to ask the question, is how much did you pay for the sensor?
#27
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Year: 2000
Model: Cherokee
Engine: 4.0L
Well, most auto parts stores will lend you a fuel pressure gauge. (They make you buy it to a credit card, then when you return it, they credit your card back.) Connect it to the Schaeder valve (under the black plastic dust cover) on the fuel rail to test.
I can imagine your original issue being a combination of weak battery and weak fuel pump. No gas -> engine stall -> alternator slows -> alternator voltage dips. Whatever the cause the electrrical is better, but maybe another issue is still there. Either way, testing the fuel pressure is relatively easy and free.
Oh, and just for good practice, when I clean my ground connections, I also like to check/clean the (+) terminal at the battery, the starter, and the alternator.
I can imagine your original issue being a combination of weak battery and weak fuel pump. No gas -> engine stall -> alternator slows -> alternator voltage dips. Whatever the cause the electrrical is better, but maybe another issue is still there. Either way, testing the fuel pressure is relatively easy and free.
Oh, and just for good practice, when I clean my ground connections, I also like to check/clean the (+) terminal at the battery, the starter, and the alternator.
After spending most of the morning meticulously gowing over all the grounds in the previously posted video and double checking all of the plugs I could find. My jeep seems to be running a lot smoother at idle, the throttle response even seems better this may be my imagination though lol however I just drove it on the freeway about 7-8 exits and she was running like a top, I stopped on the off ramp to turn around and head home happy as can be because I figured my issue was gone when it just flat out dies... won't fire for the first 3-4 attempts to restart then on the 5th crank I held it a bit longer and she started to spit and sputter as if it was trying to fire then finally the 6 crank she's alive and running smooth I got it back home with out a hitch. Turn it off and same thing hard to start... could it be the ground cleaning was only one of my issues could a bad ground caused the fuel pump to start to fail (no idea what brand fuel pump is in it, I know it was changed a little over two years ago by the previous owner) I'm leaning toward the fact I may have had more than one issue going on. Any thoughts would be much appreciated.
#28
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Year: 1999
Model: Cherokee
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I did a fuel pressure test, when I turned the key on the fuel pressure did not come up then cycled the key tell I got fuel pressure it came up to about 40psi then drops right back down to 0psi then I started it. It held pressure at about 47-48psi while running it drops a to about 44-45psi when I run the throttle up to about 2500rpm when I shut it off the pressure drops to 0psi immediately.
Last edited by Brian Day; 09-20-2017 at 10:39 AM. Reason: Spelling errors
#29
Just put fuel pump on 05 Cherokee 4.7 because of lack of pedal response and starting issues. It ran fine for 45 miles now want start people are telling me crankshaft position sensor trying to get some info from your guys it'll only turn over will not crank NEED HELP ASAP ONLY VEHICLE
#30
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Just put fuel pump on 05 Cherokee 4.7 because of lack of pedal response and starting issues. It ran fine for 45 miles now want start people are telling me crankshaft position sensor trying to get some info from your guys it'll only turn over will not crank NEED HELP ASAP ONLY VEHICLE