myjeepbreaksalot

My 2000 jeep Cherokee sport with a 4.0 began misfiring randomly once I got around 50 mph and once I hit 70 it started misfiring more often and the rpms dropped like a rock and shot back up and the check engine light flashed for a second. After that happened my fuel gauge quit working. I got off the highway and then just cruised 50 on the back roads and my fuel gauge came back to life and the misfires stopped.

Has as anyone else heard of this issue?

Willys55

could be a loose ground, flashing cel normally means that it is a multiple cylinder missfire or even one or two cylinders dropping out, if the light went out and did not come back on, you can still check with a scan tool for a code. Could also be a fuel pump or fuel filter that is plugging up. Start by checking for the stored code.

myjeepbreaksalot

Soery I meant it flashed one time in a split second and disappeared after a hard misfire. I checked it with my scan tool and there were no codes present, not even in history codes so I'm not sure. From what I've been told I should replace both my crank position sensor and can position sensor with mopar parts. I'm not sure if mine are mopar or not I only bought this Cherokee a few months ago.

tjwalker

The temporary loss of fuel gauge may be a clue as it has been tied to crankshaft position sensor failure.

With the lack of any stored codes, I would consider swapping out your crank sensor for a MOPAR OEM unit if you can find one (they are getting to be hard to locate).

I wouldn't swap out the cam sensor yet. One thing at a time is the most prudent strategy (and least expensive) and the crank sensor is more probable as a cause than the cam sensor.

Good luck and keep us updated!

myjeepbreaksalot

Thanks both of you for the ideas! My father bought me both a mopar cam sensor and a blower resistor for Christmas because I wanted extra parts for my other Jeeps and I found a mopar crank sensor I can get so I'll probably go ahead and replace both. I'll let you know how it goes once I get them on.

tjwalker

I'd recommend one at a time. Then see if it resolves. Replacing multiple parts at once can actually complicate things.

myjeepbreaksalot

thats what I intend to do. I'd prefer to pinpoint the problem rather than have 3-4 different options.

drewactual

also, pull a spark plug and read it... if its color coincides with a lean burn, look to the fuel pump and filters (if any).

Willys55

please remember to post back whether it is repaired or not, and what was done......check the grounds on the right side of the engine block.....crank sensor not related to fuel gauge.

tjwalker

Actually, a crank sensor failure can be related to the fuel gauge, as strange as it seems. I've personally seen it multiple times. Search and you'll find a number of threads that confirm this. I put a link to one of them below. Crank sensor failure can result in the drop out of both the fuel gauge and the voltage gauge.

If the crank sensor failure is a hard fail, I remove the crank sensor connector and take it out of circuit; then see if the gauge function returns. If it does, that is enough of a smoking gun right there to warrant replacing of that sensor. That isn't possible for this OP as the problem is intermittent, but it is a troubleshooting technique that I have successfully used when the gauge symptom is present.

https://www.cherokeeforum.com/f2/can...-still-123273/

roarko

Had stumbling at 45 mph, my mechanic heard faint sound in distributor, changed part smoothed out

myjeepbreaksalot

I won't have time to fix it till Monday but I will let you all know what the fix was. And I've had issues like this when I was trying to get a key cut for my older 2001 Cherokee. The fuel gauge wasn't working and I had a full tank of gas and a no bus code. The first thing I did was replace the crank sensor and everything worked fine.

jordan96xj

I can confirm that this is true. I helped a neighbor with his 2000 XJ CPS issue, and the symptoms were exactly as described above. We could disconnect the CPS and the fuel and voltage would come back to normal. Replaced CPS resolved the no-start and gauge problems.

myjeepbreaksalot

With a new crankshaft position sensor in the Cherokee it won't even start. It is a oem sensor as far as I know. It did throw a code that said intermittent loss of the crank or cam sensor.

tjwalker

Is it an actual MOPAR crank sensor? Where did you buy it and what did you pay for it? There is no lack of sub-par quality crank sensors for sale.

You could put in your old one as a test as that one gave you only intermittent symptoms. If your XJ starts with your old crank sensor, then the new sensor you had put is is DOA.