View Full Version : Flywheel Flex Plate
hey fellas
Does anyone know what a cracked flex plate would sound like. I had the auto transmission rebuilt and they replaced the TC with a rebuilt/new one so that should be fine. I hear this ticking noise from there and it only ever happens when i idle. When im driving theres no noise.
Im sure the noise isnt an exhaust leak (checked everywhere), i had my valves adjusted (2,000kms ago), i have new penrite HPR30 oil in there which is nice and thick.
Im positive that the noise is coming from the the TC area because i used a garden pipe to listen around and the noise comes loudest from the peak hole.
Ive searched on around and no one has had the same issue.
EDIT: post 7 has video
Blitzkrieg Bob
04-07-2009, 03:22 AM
Not the flex plate.
take it back to the shop and have them check it out.
there should not be any noise from the TC.
Yeah i'm contemplating taking it back. Technically they should have also checked the flex plate for any cracks and stuff right?
Blitzkrieg Bob
04-07-2009, 03:27 AM
If the flex plate was cracked, you'd really hear on starting and under load. Since thats holding the TC & ring gear too.
Hmmmmm okay the noise only ever happens after the car is warmed up and idling.
Binjammin
04-07-2009, 04:29 AM
Crawl under the car and check to see that the torque converter bolts are tight.
heres a video of the noise
http://www.youtube.com/watch?v=_D1Z9tbKdxA
Binjammin
04-07-2009, 06:07 AM
Yeah, I'd tighten up those torque converter bolts.
Yeah, I'd tighten up those torque converter bolts.
I hope to God your right.
Ill kill myself if it was rod knock or something srs like that.
UPDATE: TC bolts were tight. I snugged them up a bit more and no difference.
I just took my car to the shop who rebuilt it and he reckons its one of my engine bearings or tappets..........this is when i had a wtf look on my face as according to him its not the transmission.
I then took the car to my mechanic who does some work on the car. I told him to chuck the car up on his hoist and have a listen. He reckon no way in the world is that rod knock or engine bearings. Then we used a garden hose and had a listen around. If you point the hose towards the engine in the bellhousing peak hole you hear nothing. If you point it towards the transmission side you hear the tick tick tick. So my mechanic reckons its the transmission.
So now i took my car around to another auto transmission shop to get there opinion but sadly there were fully booked so i have to go there tomoz morning. Im interested to hear what their opinion is.
Okay new update
The other transmission shop i went to this morning said its not the engine or transmission but could be the flex plate..... so once again im left guessing.
Maybe my oil pressure at idle is low......
i dunno..... im over it..........
russiankid
04-08-2009, 08:48 PM
Mine ticks but not that loud. That is definitely not engine noise.
The oil im using for the engine is fine.
I had 15w40 in there. Noise still existed.
Last week i put in some 20w60 semi-syn oil and the noise is still there.
Both weight of oil are good for the climate i live in.
Up top the engine noise is the usual m30 sewing machine sound. Valves like i said were adjusted just recently and had quieted down the valves a bit. You can hear the injectors ticking away too but they have a different tick. Then under all those noises you can still hear the annoying ticking coming from down low.
i wonder why the noise doesn't happen when cold though.... when cold you would hear rockers/rod knock/piston slap/etc a lot more right? Then when the engine is warm expansion of the metals help make those noises disappear and not to mention that the oil is thinner and able to pumped around better....... meaning better lubrication.
The noise is somehow amplified i the bellhousing. Its the only place where you can hear it from. Ive stuck a screwdriver/hose everywhere on the engine block and theres no ticking from the engine. Ive done the same to the transmission. Both dont re-produce the same noise from the bell housing.....
btw if i did have low oil pressure wouldnt the idiot light come on or flicker?
What about this i found in the bentley manual
http://i254.photobucket.com/albums/hh89/arnzlozz/bearing.jpg
filmy
04-09-2009, 01:00 AM
In listening to your video, the only time I could hear the ticking is upon deceleration. Is that the case?
In any case, I doubt it's your flex plate. A previous poster was correct that you'd hear it big time during using the starter - and even then, the plate would have to be hitting against something to make that noise. When the engine's turning, there's nothing coming in contact with the rotating flex plate (except the TC, of course). And I don't know what a bad pump in a BMW auto tranny sounds like, but I don't think it would be "ticking".
Off the wall, but have you checked for an exhaust leak? Even up top? I had an exhaust leak from a Chevy 350cid header gasket that sounded like a bad rod bearing, until we decided where the actual noise was coming from. And that noise might be transferring down the downpipe. Just a thought...
In listening to your video, the only time I could hear the ticking is upon deceleration. Is that the case?
In any case, I doubt it's your flex plate. A previous poster was correct that you'd hear it big time during using the starter - and even then, the plate would have to be hitting against something to make that noise. When the engine's turning, there's nothing coming in contact with the rotating flex plate (except the TC, of course). And I don't know what a bad pump in a BMW auto tranny sounds like, but I don't think it would be "ticking".
Off the wall, but have you checked for an exhaust leak? Even up top? I had an exhaust leak from a Chevy 350cid header gasket that sounded like a bad rod bearing, until we decided where the actual noise was coming from. And that noise might be transferring down the downpipe. Just a thought...
Yep the noise only ever happens on deceleration. Or when it has no load on the engine/drive train.
Ive checked for exhaust leak and i'm positive in saying that theres none. Ive started it up cold and felt around and no pulsating air can be felt. Ive also done the same hose method of listening around the manifold...
rinodattilo
07-10-2010, 01:51 AM
Did you ever figure the noise out??? I just did a rebuild on my 735i and we put it all together, the mechanic left for Europe for a month and I have the same exact noise! Cannot believe I found your post. Please let me know what you found!
godzilla12
10-31-2013, 07:22 PM
I had my transmission on my 1999 328i rebuilt with tc changed. After about three weeks I started hearing a knocking sound coming from the transmission. The noise is heard while the engine is idling and stops when the vehicle is revved to 2000 or more rpm. I took it back to the garage and they removed the transmission and found the drive plate broken. I bought a new drive plate and had them install it. The noise stopped. After 2 weeks the noise came back. They took down the trans again and found the drive plate broken again. The job is under warranty so they have to replace the drive plate this time. I'm puzzled as to why two drive plates were broken. I'm thinking its poor workmanship. I hope they get it right this time
Powered by vBulletin® Copyright © 2025 vBulletin Solutions, Inc. All rights reserved.