onyx82

Hey I have a 98 XJ that was making the typical flexplate sounding knock. I replaced the flexplate and the starter and it still has the same knock coming from the bell housing area. I have to say I am at a loss as to what it could be now. Any ideas? Thanks.

Firestorm500

Well, it wasn't the flexplate.

Get a mechanic's stethoscope and try to pinpoint the area of greatest noise. Be careful around a running engine.

1976Mustang

Piston knock in one of the rear cylinders. I though the same thing, then realized i don't even have a flex plate (5-speed manual)

And adding onto Firestorms post, a long screwdriver will do just fine ;-)

1976Mustang

To help you out, skip to 1:27 in this video, does that sound like the knock you have?

onyx82

Thanks for all the input I'll check it further in the am. The sound in the video is pretty close yes.

onyx82

Well it sounds like possibly a rear cylinder knocking. Great.

onyx82

OK after more time under the jeeo I am more confused about this sound than I was before lol. The knocking doesn't get faster when u give it gas it just goes away. The sound is louder in the jeep than it is outside. To hear it good outside you have to stick your head next to the vent below the windshield. I have now replaced the flex plate, starter, and serviced the transmission. Sounds like someone slowly tapping their knuckle on a piece of wood. I'm now at a complete loss to explain it.