Code P1391, Replaced plugs wires and cam sensor, runs worse
#1
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Year: 1996
Model: Cherokee
Engine: 4.0L 6CYL
Code P1391, Replaced plugs wires and cam sensor, runs worse
I have a 96 4.0 with a ax15 and it had been acting funny, ie not wanting to rev over 3000, stalling, and occasionally poor idle. So I was at advanced auto and the guy told me his cherokee had the same code and it was the cam sensor but they dont sell them seperate from the distributor. So I bought a dizzy and just replaced the plastic sensor looking thing which i assume was the Cam sensor. Along with that I did the plugs, wires, rotor and cap and now it will hardly run.
I checked to make sure the Firing order/wires going to the right place and everything was plugged back in right. Im guessing it might be a Crank sensor or i need to replace the whole dizzy(just didnt have time today.)
Thanks in advance.
I checked to make sure the Firing order/wires going to the right place and everything was plugged back in right. Im guessing it might be a Crank sensor or i need to replace the whole dizzy(just didnt have time today.)
Thanks in advance.
#3
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would of been quicker to replace the whole dizzy.
Is probably a clogged cat, sounds like other issues now since you took a new distrbutor apart, and put parts in your old one.
What kind of plugs are your running.
Is probably a clogged cat, sounds like other issues now since you took a new distrbutor apart, and put parts in your old one.
What kind of plugs are your running.
#4
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Year: 1996
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Im just running some accel copper cores, they came as a kit with the wires, cap and rotor for cheap. I know NGKs and Champs would be better but couldnt pass up a good deal.
How does one go about the clogged cat issue? Just replace both or would it be the upstream one? downstream? Any way to fix it without buying a new one?
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Year: 1999
Model: Cherokee
Engine: 4.0
I have a 96 4.0 with a ax15 and it had been acting funny, ie not wanting to rev over 3000, stalling, and occasionally poor idle. So I was at advanced auto and the guy told me his cherokee had the same code and it was the cam sensor but they dont sell them seperate from the distributor. So I bought a dizzy and just replaced the plastic sensor looking thing which i assume was the Cam sensor. Along with that I did the plugs, wires, rotor and cap and now it will hardly run.
I checked to make sure the Firing order/wires going to the right place and everything was plugged back in right. Im guessing it might be a Crank sensor or i need to replace the whole dizzy(just didnt have time today.)
Thanks in advance.
I checked to make sure the Firing order/wires going to the right place and everything was plugged back in right. Im guessing it might be a Crank sensor or i need to replace the whole dizzy(just didnt have time today.)
Thanks in advance.
P1391 is intermittant loss of Cam Sensor or Crankshaft Position Sensor signal to the PCM.
Possibile causes are:
DAMAGED TONE WHEEL/FLEX PLATE (CRANKSHAFT)
DAMAGED TONE WHEEL/PULSE RING (CAMSHAFT)
INTERMITTENT CKP (CPS) SIGNAL LOSS WHEN WIRING IS WIGGLED
WIRING HARNESS INTERMITTENT
INTERMITTENT CMP (CAM SENSOR) SIGNAL LOSS WHEN WIRING IS WIGGLED
SENSOR CONNECTOR/WIRING
SENSOR CONNECTOR/WIRING
CAMSHAFT POSITION SENSOR
CKP SENSOR CONNECTOR/WIRING
CRANKSHAFT POSITION SENSOR
DAMAGED TONE WHEEL/PULSE RING (CAMSHAFT)
INTERMITTENT CKP (CPS) SIGNAL LOSS WHEN WIRING IS WIGGLED
WIRING HARNESS INTERMITTENT
INTERMITTENT CMP (CAM SENSOR) SIGNAL LOSS WHEN WIRING IS WIGGLED
SENSOR CONNECTOR/WIRING
SENSOR CONNECTOR/WIRING
CAMSHAFT POSITION SENSOR
CKP SENSOR CONNECTOR/WIRING
CRANKSHAFT POSITION SENSOR
Last edited by CCKen; 09-10-2012 at 07:28 AM.
#6
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Year: 1996
Model: Cherokee
Engine: 4.0L 6CYL
Here's a Youtube vid to view: How-To Test a Crank Shaft Position Sensor CPS - YouTube
P1391 is intermittant loss of Cam Sensor or Crankshaft Position Sensor signal to the PCM.
Possibile causes are:
P1391 is intermittant loss of Cam Sensor or Crankshaft Position Sensor signal to the PCM.
Possibile causes are:
DAMAGED TONE WHEEL/FLEX PLATE (CRANKSHAFT)
DAMAGED TONE WHEEL/PULSE RING (CAMSHAFT)
INTERMITTENT CKP (CPS) SIGNAL LOSS WHEN WIRING IS WIGGLED
WIRING HARNESS INTERMITTENT
INTERMITTENT CMP (CAM SENSOR) SIGNAL LOSS WHEN WIRING IS WIGGLED
SENSOR CONNECTOR/WIRING
SENSOR CONNECTOR/WIRING
CAMSHAFT POSITION SENSOR
CKP SENSOR CONNECTOR/WIRING
CRANKSHAFT POSITION SENSOR
DAMAGED TONE WHEEL/PULSE RING (CAMSHAFT)
INTERMITTENT CKP (CPS) SIGNAL LOSS WHEN WIRING IS WIGGLED
WIRING HARNESS INTERMITTENT
INTERMITTENT CMP (CAM SENSOR) SIGNAL LOSS WHEN WIRING IS WIGGLED
SENSOR CONNECTOR/WIRING
SENSOR CONNECTOR/WIRING
CAMSHAFT POSITION SENSOR
CKP SENSOR CONNECTOR/WIRING
CRANKSHAFT POSITION SENSOR
He says in there somewhere though that if you get spark at all then your CPS is good. Is that true? Theres no in between?
#7
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Year: 1999
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Actually that's the wrong vid for your problem, albeit a good vid for no start problems. Go to Youtube and look for a vid on checking Hall Effect CPS'. I saw it once and it's pretty good. Checks your CPS while cranking and running. There are several vids on Hall Effect CPS testing which suck but there's one really good one. Check it out.
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#9
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Year: 1996
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Well, replaced the dizzy put it back togeter and wouldn't even start. Lined up the dizzy just like the old one was. Put the wires back on just like the diagram shows. Turns out the wires were all one plug counter clockwise so the dizzy must have been put in a tooth or 2 backward. Everything runs great now and revs up fine and is much better. Thanks for your help guys. Now on to front axle u joints...
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