1999 TJ has a fluttering / clacking sound in drive and sometimes in park

H_E_H

TJ Enthusiast
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Hello Folks,
1999 TJ automatic with ~180K miles
Any insight what's making this fluttering/clacking sound when we put our TJ in Drive? The rate of fluttering/clacking increases with acceleration.
Doesn't appear to impact driving, but does make a lot of noise. I've searched a bit and found timing chain replacement and tightening the bolts on the flex plate.
Thanks in advance for any insight and help.

Here's a video:
 
Sounds like a rod bearing. I wouldn't be driving it around until it gets fixed or you may be replacing the motor.
 
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Sounds like a rod bearing. I wouldn't be driving it around until it gets fixed or you may be replacing the motor.
Okay, noted. I"ll be doing some research. we were driving it around yesterday and the noise was gone!
Thanks for the insight! Nice ride
 
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Okay, noted. I"ll be doing some research. we were driving it around yesterday and the noise was gone!
Thanks for the insight! Nice ride
Since you mentioned the noise went away, piston slap is possible, which tends to diminish after it warms up. Broken piston skirt is another possibility.
You need a stethoscope or piece of pvc to carefully listen and pinpoint the area it's coming from. From the video it appears to be coming below the head and maybe one side of motor. It's hard to tell from here.
 
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Okay, I'll give a listen with PVC pipe (my youngest is a fisherman and he had some leftover PVC from making pole holders for the beach!)
 
Okay, I'll give a listen with PVC pipe (my youngest is a fisherman and he had some leftover PVC from making pole holders for the beach!)
Pole holder diameter is to big. You want like 1/2" and rest it against the motor away from fan and the other end squeezed in your hand up against your ear. You can use an extension, steel rod or long screw driver as well but then you need to stay away from hot wires. Personally, I always used a long 1/2" extension. You're basically trying to get a better idea of location and the sound itself.
 
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Pole holder diameter is to big. You want like 1/2" and rest it against the motor away from fan and the other end squeezed in your hand up against your ear. You can use an extension, steel rod or long screw driver as well but then you need to stay away from hot wires. Personally, I always used a long 1/2" extension. You're basically trying to get a better idea of location and the sound itself.
Ahh, okay. Understood. I'll get one! Thank you again
 
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I believe I solved the issue: 2 of 3 loose fly wheel bolts!
I will go back in there and secure them with some lock tite ASAP.
Thanks for the help, flyinfish!
 
I believe I solved the issue: 2 of 3 loose fly wheel bolts!
I will go back in there and secure them with some lock tite ASAP.
Thanks for the help, flyinfish!

Well done! And a cheap fix.

Since you have an automatic it's a flex plate and the bolts go into the torque converter. You'll want to inspect the holes in flex plate to make sure they're not oblong and if it were me I'd replace the bolts. The bolts have been taking a beating and they're not expensive.
 
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Well done! And a cheap fix.

Since you have an automatic it's a flex plate and the bolts go into the torque converter. You'll want to inspect the holes in flex plate to make sure they're not oblong and if it were me I'd replace the bolts. The bolts have been taking a beating and they're not expensive.

Cheap fix, indeed! Flex Plate and torque converter - understood and thanks for the correction. I had indeed read/heard the holes may be worn oblong, but upon inspection, that luckily wasn't the case. Okay, I will purchase new bolts. I tried reading the TJ's codes with a scanner at Autozone (no codes came up) and noticed the mechanics stethoscope and just picked it up rather than the PVC pipe. Thank you again for the assist, flyinfish.
 
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Hey All,
I'm replacing the torque converter bolts. Replaced the first one, no problem. I removed the second bolt, but cannot get the new bolt in because its hole is now misaligned. I rotated back to the first bolt and loosened it up hoping to get some play to realign the second bolt's holes, but that didn't help. Neither die loosening the third bolt. What else can I attempt to have the holes line up properly? Thanks


EDIT: I've now tightened up the two bolts and the third bolt's holes don't seem so severe in misalignment. Screwing in the third and the bolt is at an angle. Could I continue tightening it down, hoping it will align everything once firmly screwed in? Or could forcing the bolt strip its threads?
 
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Hey All,
I'm replacing the torque converter bolts. Replaced the first one, no problem. I removed the second bolt, but cannot get the new bolt in because its hole is now misaligned. I rotated back to the first bolt and loosened it up hoping to get some play to realign the second bolt's holes, but that didn't help. Neither die loosening the third bolt. What else can I attempt to have the holes line up properly? Thanks


EDIT: I've now tightened up the two bolts and the third bolt's holes don't seem so severe in misalignment. Screwing in the third and the bolt is at an angle. Could I continue tightening it down, hoping it will align everything once firmly screwed in? Or could forcing the bolt strip its threads?

Get each bolt in and leave them just loose enough that the converter can still move independent of the flex plate. Continue until they're all in then tighten them.
 
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I removed all four bolts and now none of the holes line up (the bolts have not threads to grab onto) Arrgh. Hope I didn't make a small task a more involved one.
 
Through the larger holes on the flex plate, I'm able to rotate the torque converter with my fingers, yet locating the bolt holes on the torque converter has been elusive. As I rotate the torque converter, I can see when a raised section passes by the bolt hole, yet I'm not seeing a threaded hole to line up with the flex plate's hole. Could the torque converter have shifted when I removed all four bolts? I'm stumped what to do. Any insight is appreciated. Thanks
 
The torque converters pads that have threaded holes should be very close to the flex plate holes. Post a pic or two because once you make sure the converter is up against the flex plate and put a bolt in, it should be rotate, repeat and then a round of tightening.
 
The torque converters pads that have threaded holes should be very close to the flex plate holes. Post a pic or two because once you make sure the converter is up against the flex plate and put a bolt in, it should be rotate, repeat and then a round of tightening.

I was able to line up the holes, but something's happened with the torque converter. As if it's somehow moved away from the flex plate? The bolts now don't seem long enough to grab hold of the threads on the torque converter?!?
 
I rotated the torque converter and tried a different hole. The bolts are now too short. I'm thinking of purchasing longer bolts to pull the torque converter closer and attempt to grab with the correct bolts. EDIT: Couldn't locate longer bolts. Not sure how to pull the TC closer towards the plate
 
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