Rod knock, maybe?
02-09-2009, 02:46 PM
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Rod knock, maybe?
My jeep, literally today just started doing this. I was parked and all of a sudden I hear this fast paced knocking, I'm like oh great. 
It's not valvetrain ticking, it's knocking coming from the bottom end. Not sure what it is. It's fast-paced at idle, and when I give it gas it gets quicker (i think - it's hard to tell because the stupid fan clutch gets louder too lmao). Any ideas? Car has 230k miles. Oil pressure seems fine (idles around 25psi when very hot (driving for an hour or so) and cruising oil pressure is like 45. Oil was changed a few weeks ago. Help 
It's not valvetrain ticking, it's knocking coming from the bottom end. Not sure what it is. It's fast-paced at idle, and when I give it gas it gets quicker (i think - it's hard to tell because the stupid fan clutch gets louder too lmao). Any ideas? Car has 230k miles. Oil pressure seems fine (idles around 25psi when very hot (driving for an hour or so) and cruising oil pressure is like 45. Oil was changed a few weeks ago. Help
02-09-2009, 04:00 PM
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Year: 1991
Model: Cherokee
Engine: 4.0 I6
You have an inspection plate where the starter is bolted. Remove the started then the inspection cover then chalk the tires and put on the ebrake, then toss the jeep in neutral. You will have to pry the flexplate/flywheel or what ever you want to call it to turn it and check the bolts. If they are lose use some thread locker and retighten them. You can also make sure the flex plate itself is not cracked.
02-09-2009, 04:04 PM
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idk it just sounds like a steady fast knock. louder from underneathe the car. a buddy of mine had loose flexplate bolts (on a different vehicle) and it made all sorts of weird noises, not this steady knock that gets faster at higher rpms \=
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02-09-2009, 04:47 PM
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Year: 1990 laredo
Model: Cherokee
so I have been searching on naxja for the search terms "torque converter bolts"
This seems to be a very well documented problem (TC bolts loosening, sometimes totally going MIA), with symptoms where the owner thinks it's a rod knocking or stuck lifter. There was one thread where the guy bought a replacement for his engine with a rebuild, only to find the torque converter bolts were less than hand tight on removing the original engine.
I would certainly not overlook this as a failure here could be nasty. I will personally be checking mine first thing. I am praying that they are loose- I would rather spend a little time laying under my XJ with a 15mm wrench than emptying my pockets on a rebuilt short block.
call me crazy..
This seems to be a very well documented problem (TC bolts loosening, sometimes totally going MIA), with symptoms where the owner thinks it's a rod knocking or stuck lifter. There was one thread where the guy bought a replacement for his engine with a rebuild, only to find the torque converter bolts were less than hand tight on removing the original engine.
I would certainly not overlook this as a failure here could be nasty. I will personally be checking mine first thing. I am praying that they are loose- I would rather spend a little time laying under my XJ with a 15mm wrench than emptying my pockets on a rebuilt short block.
call me crazy..
02-09-2009, 04:53 PM
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Year: 1991
Model: Cherokee
Engine: 4.0 I6
Yep when I replaced my motor they were tight but after replacement they losened up..I added some red lock tight and so far they have held very well.
02-09-2009, 06:02 PM
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True, I started the car up again after sitting about an hour and it wasn't doing it anymore lol. Only once in a while like every 5 seconds, and then took it for a spin and stopped completely. Im sure itll arise again, probably TC bolts lol. We'll see. Maybe it fixed itself? 
02-09-2009, 07:05 PM
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Year: 1991
Model: Cherokee
Engine: 4.0 I6
True, I started the car up again after sitting about an hour and it wasn't doing it anymore lol. Only once in a while like every 5 seconds, and then took it for a spin and stopped completely. Im sure itll arise again, probably TC bolts lol. We'll see. Maybe it fixed itself?
02-09-2009, 07:25 PM
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Year: 1987
Model: Cherokee
Engine: 4.0 soon to be gc ho 4.0
i had the same noise described in my pickup....it ended up being a wrist pin// dont know how it worked loose...132,000 miles on it never ran hard. well real hard lol x2 i would check what everyone else has already told you. if nothing fixes it then i guess it will stay noisy till you get a suprise know and abrupt silence...lol hope you get it figured out.
02-09-2009, 07:47 PM
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i had the same noise described in my pickup....it ended up being a wrist pin// dont know how it worked loose...132,000 miles on it never ran hard. well real hard lol x2 i would check what everyone else has already told you. if nothing fixes it then i guess it will stay noisy till you get a suprise know and abrupt silence...lol hope you get it figured out.
lol thanks man.. i hope its not the motor )=