tristoncook7788

Hello everyone, I'm Triston and I own a 1992 Chrysler Jeep Cherokee XJ 2wd 4.0HO automatic with 119k miles that was given to me by my great grandmother last year under the conditions I fix it up and don't sell it.
I had it running good enough to daily it this past year but have run into some trouble. If anyone is willing to help I will be very grateful and will pay it forward on these forums.

I figure I'll include the most pressing issues in this thread
1) Knocking sound. Doesn't seem to get louder with rpm or load. Here are 2 videos of the knock, one showing the long crank time. https://youtube.com/shorts/_brNB8cOSL8?si=EwFWhVdTaGxb3C9J
https://youtu.be/Rbin_2X3VYs?si=1wVFO2PHQz7BJmGw
2) today it started bucking/jerking harder than normal when accelerating, and now lopes at idle when hot. Long crank times. Cycling key does not have an effect. https://youtube.com/shorts/DIyyxmJQDwU?si=ULzAor9xkQuXVSDD (idle lope)
3) Carfax says it's due for a trans band adjustment at 120k. Dealer and shops around here claim the jeep is too old to work on so I'm stuck doing it myself. I have no idea how to do this.

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lawsoncl

Um, what's with the clothes pins on the fuel line?

Don't worry about the transmission. I'd suggest taking the cover off the front of the bellhousing and check that the torque converter bolts are tight. That might be the knocking at idle.

KoboldKrawler

Holy moly, I missed that first watch, no kidding, buddy, might want to sort out why someone was doing laundry with your engine bay. I would also check the torque convert bolts as well.
How are the engine mounts? Bucking could be a sign of bad mount bushings.
Maybe clean out your Throttle Body as well, could explain the rough idle.
Check your CPS (crank position sensor) as well. Those are notorious for troubles on these old jeeps. Buddy of mine keeps spare ones in his glovebox. LOL

cruiser54

https://www.cherokeeforum.com/f51/ho...ocking-125547/

tristoncook7788

That's the exact noise I have! I'm gonna try and get that taken care of some time this weekend if it dries up. Doesn't the crank sensor read off of the flex plate, so that might cause it to lope?? Also the starter hangs up sometimes, could be explained by a loose flex plate maybe. I think you guys just fixed several of my issues.
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The clothes pins were an attempt at fixing the no start when hot issue my grandma was having a few years ago. I don't remember if that fixed it or not but I also cleaned the throttle body around that time And did some other things. Plus, if I ever need a pin I know where to find one!

The engine mounts seem sturdy. Slight movement when revved. The rpm also changes relative to the bucking, and only does it when hot like the loping. Sometimes it also drops an entire cylinder at idle when hot. I will try and get to the cps and throttle body this weekend. It's only been 10k miles since cleaned but the intake seems to get dirty quickly.

Thanks guys! I'll keep checking the thread in case anyone has more suggestions and I'll post an update as soon as I can get to it. Might be sometime next week.
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cruiser54

Concentrate on the knock/flexplate bolt issue first.

robsjeep

What is with a transmission band adjustment, I dont think that has ever been done on mine, at over 300k miles. Is that a XJ required thing for the AW4 tranny?

lawsoncl

While you're looking at the flexplate and verifying the flexplate-to-torqueconverter bolts are tight, look up towards the center with a flashlight while you pry on it a little. You're looking to see if it's cracked. Yes, the crank sensor reads off the windows in the flexplate. This could be a failing crank sensor as one symptom if they get weak is difficultly starting.

cruiser54

Not applicable to the AW4.

tristoncook7788

So I finally got around to working on the Jeep. Flex plate seems fine, bolts are tight and no cracks. Tightened battery cables helped with the loping and it starts alot faster. Just can't figure out that knock. Though I did notice where the exhaust bolts up to the manifold the exhaust is dented in, maybe it's leaking making that sound?

lawsoncl

The dent in the exhaust pipe is normal. Comes from the factory that way.