Ok...still getting the p1391 engine code after changing the crankshaft position sensor, still running like crap! Help?
Does your Cherokee have a cam sensor or distributor cap? If you are not familiar with them, then the easy way is.. does it have spark plug wires or coils on top of the plugs?
Cam sensor.... take it off and see if the pick-up is bent.. happened on my 2000 TJ 4.0
The cam sensor is $50 something, but the entire oil pump drive unit is like $65 and comes with a new cam sensor also. You solve 2 problems at once.... the cam sensor and the problematic oil pump drive gear.
Distributor... check the rotor and cap for cracks and carbon tracking. Even new ones can be bad. Check the wires and see if there is any white marks on them where they touch something or eachother ... if so, they are arching through the wires and need replaced or convoluted tubing places around them in those areas.
Hope that helps
From my understanding and researching, my 1998 Cherokee has a pick up inside the distributor towards the bottom...still need to clean throttle body and iac, so perhaps I'll pull the distributor cap off and perform a visual inspection.
Another thing is, a guy used his own basic code reader and says my jeep is posting a p0301 code as well however I yet to pick that code up with my reader.
p0301 is a cylinder 1 misfire. Check the plugs and wires for wear, shorting out, etc. Id make sure to pay close attention to cyl 1 if it had that code. Also check all the wiring and connectors for the CKP and CMP sensors. Be sure theres no frayed/broken wires, or oil in the connectors. Also, fwiw, Chrysler products love Champion spark plugs. Use whats specified as the factory plug. Used to fix ALOT of misfires when I worked for a Chrysler/Jeep dealer here in Ft Wayne by just putting the right plugs back in. I never would have thought a brand of plug would have made such a difference had I not seen it so many times myself
Sometimes just breaking a connecting and remaking it will restore conductivity, can't remember what it's called but learned about that in college (diesel program). These old computers make diagnostics a challenge, few specific codes so you do a lot of part testing and wire checks. Re: your slight misfire, is this just at idle? You don't have a cracked exhaust manifold do you? I've seen that confuse the O2 sensor at idle.
Btw, I'm in Columbus too.
I don't hear an exhaust leak, mostly noticeable at idle but can notice a miss at higher RPM's...I yet to clean the throttle body, the IAC sensor, and throttle position sensor. I may run injector cleaner when I get more gas in a bit...
Just because you have new plugs and wires that doesn't mean you have all new good plugs and wires
First thing I do when I have a miss is swap stuff out, see if the miss moves.
Not sure of your ECM, but after changing stuff I unplug my battery on my ZJ and let it clear, then fire it up and let it re-learn (my Grand fouls a plug over time- do this once or twice a yr).
And yes, I have had a new plug wire bad from the factory.
Got my XJ looked over today, after three years of ownership, I know what is not wrong now. I heard a noise from the front it (a few, but hey, it is a Jeep). I thought my wheel bearings were going bad. Turns out, it is just tire noise and axle turnign noise.
Now I am going to go off roading on Saturday with no fear of breaking an expensive part.
We should nuke China and Mexico just because of that.
You are wheeling a Jeep aren't you?
Quick question on my 4.0L...if I wanted to change the tone of the exhaust, how can I do so without reducing my mileage providing my driving habits remain the same? I've thought about cutting the stock muffler off and adding a dynomax muffler to give my jeep a deeper, tab bit louder sound over stock muffler but I don't want to lose power or mileage.
One of the best sounding exhausts Ive heard is the one I have on my 4.0 YJ which is a flowmaster 40. It actually helps my mileage slightly. Just add a different muffler but make sure to keep your exhaust a full run to the rear.