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View Full Version : Help! What the hell is wrong with my AEB



LowSantorin
03-23-2009, 09:02 PM
So on friday i pulled flashing CEL and the car died. Was running very ruogh before it died and had a knock/ticking. It started and would run but very rough. So i scan it today and pull up a cylinder 4 misfire. Fixed that and put new valve cover gaskets in today. got back in started it and i still have a very bad ticking. It sounds just like a broken valve on a normal 4 bolt main 350. Took the valve cover back off and turned it over looking for broken springs/lifter etc. Couldn't see anything in there that looked wrong. I might be pulling the cams and going from there tomorrow. Any ideas you guys have? Anything i should check befre going in deeper in the motor? Thanks

Update
Got the lifters fixed and the motor back together. Also decided to do a new timing belt while i was in there, the old one had ~40k on it. Got everything installed and starts and runs but it is running rough. Also i have a horrible whining now coming from the front (timing belt) area. Im stumped need some experts here

LowSantorin
03-23-2009, 09:16 PM
oh yea its early 99 AEB with about 130k

jrock
03-23-2009, 10:11 PM
Let me know if you need any spare engine parts...

Beemer832
03-24-2009, 08:07 AM
check the cam chain tensioner. mine went out and it sounded something like what your describing. the NON electronic one (cant think of the damn name) is big $$$ but if you have AEB it is oil pressure driven and its only about $100~ from ecstuning and the like.


I had a video of the noise mine was making but the damn car isn't quiet so its kind of hard to hear.

video quality is poor and its dark but camera is right about the valve cover where the cam chain tension sits.

http://www.youtube.com/watch?v=CUdOm0db2Yc

good luck
-josh

Holvinator
03-24-2009, 08:38 AM
Bruu,mmm BrummMmm BruummMMMMmm lol

LowSantorin
03-24-2009, 11:45 AM
check the cam chain tensioner. mine went out and it sounded something like what your describing. the NON electronic one (cant think of the damn name) is big $$$ but if you have AEB it is oil pressure driven and its only about $100~ from ecstuning and the like.


I had a video of the noise mine was making but the damn car isn't quiet so its kind of hard to hear.

video quality is poor and its dark but camera is right about the valve cover where the cam chain tension sits.

http://www.youtube.com/watch?v=CUdOm0db2Yc

good luck
-josh

It could be that because it is right around that area. Its a lot louder than that though. How can you check it? If it was bad wouldn't it pull a cam or timing code?

Beemer832
03-24-2009, 11:53 AM
mine sounded like the chain was almost rubbing on the valve cover but after later inspection it wasn't thankfully.

also i remember starting the car one day and the engine sounded like it was knocking so bad the rod was going to go through the block :-( now this again is after i mis-shifted from 3rd to 4th and grabbed second by accident so I don't know what affect this had on it, if any.....

only way to check it is to pull it off the head. you will need the compressor tool for this FYI. DO NOT TRY TO ATTEMPT REMOVING THE TENSIONER without the tool unless you are FOR sure buying a new tensioner, and even then you may not even be able to. Just get the tool.

might as well get a new chain while your at it too. They can stretch over time and they are only about $30 from ECS tuning.

You will need a new gasket/seal set as well.

When these tensioners go bad, they have a mesh screen on the bottom side where it meets the head. This is where the oil flows and pressurizes the tensioner. If there is sludge buildup in the engine, the sludge will clog the screen and prevent oil and pressure from expanding the tensioner as its needed to help drive the cam chain.

I would try to get the cover off and inspect for an visible wear ASAP. If that chain breaks or loses all tension then you are looking a valve job, valves, and maybe even a head if somethign actually breaks...


the joys of owning an audi :-)

-josh

LowSantorin
03-24-2009, 12:04 PM
The cover off and chain looks visually fine, so you need to pull the tensioner out and inspect the bottom?

Beemer832
03-24-2009, 12:07 PM
how much tension is on the chain? it should be fairly tight, you should not be able to move the chain in the direction that it spins. pulling up on the chain should move very minimal if any at alll.

LowSantorin
03-24-2009, 01:21 PM
Chain is tight with no slop. I'm thinking it may be a lifter

Beemer832
03-24-2009, 01:22 PM
could be, never heard a bad lifter before so I am not sure what that would sound like.

-josh

Nebone
03-24-2009, 01:56 PM
Here is what a bad tensioner sounds like Click (http://www.youtube.com/watch?v=oIhKXCbuOCM)

Sound clip would be useful to diagnose.

LowSantorin
03-24-2009, 02:01 PM
I will try to get a sound clip soon, It sounds just like that however my initial inspection would say the tensioner is good. Im going to go check lifters now.

Beemer832
03-24-2009, 02:03 PM
wow that was my noise to a T...... glad i got that thing fixed. good video!

-josh

CrtchRktRcr
03-27-2009, 09:41 AM
how about this one.. u can hear it on the last part of the vid.. mine does it on cold startup (cold here is like 55*) and for like 5 to 10 seconds.. ideas? almost sounds like a power steering pump whine..

http://www.youtube.com/watch?v=3Th8jvg1E8I&NR=1

LowSantorin
03-28-2009, 08:54 PM
Replaced the lifters and the fixed the noise (knocking/ticking). Also put on a new timing belt when i was in there and now i have a horrible whine, almost sounds like its coming from the t belt itself. Any ideas guys? i think it may be the gear up and to the right of the crank gear.. What does this gear do?

GR-RALLYE
03-28-2009, 08:57 PM
the water pump?

LowSantorin
03-28-2009, 08:58 PM
No not the water pump. It's the gear the t-belt runs aorund

LowSantorin
03-29-2009, 04:38 PM
http://i32.photobucket.com/albums/d4/mx_racer_58/aebhl.jpg this one

GR-RALLYE
03-29-2009, 05:13 PM
i wanna say thats the intermediate shaft to drive the oil pump

LowSantorin
03-29-2009, 06:39 PM
^ yea your right cant believe this slipped my head[headbang][headbang]

'Im stumped now i cant figure out why the hell this thing is whining.

Any reason this area would be making a whining noise?

Could it be the belt is somehow to tight(bad tensioner or something?) and is causing the whining?

GR-RALLYE
03-30-2009, 12:01 AM
i don't think it would be cuz the belts too tight.. I'm not sure how it would come from there i think when i took mine out its held in by just a seal and a o ring so that wouldn't/shouldn't be a source of the whine?

maybe the roller by the tensioner?

LowSantorin
03-30-2009, 12:49 AM
I was thinking the roller also but already have ruled that out. I also had the idea it might be the water pump as it sits close to that gear.

I dont know if it is the belt, i know they can make noise and the belt is super tight. The thing that makes me want to rule the belt out is the tensioner is almost completely pushed in to the pinning position so i doubt its too tight and causing noise.

GR-RALLYE
03-30-2009, 01:22 AM
My only other guess would be one of the aux belts may be rubbing somewhere

LowSantorin
03-30-2009, 01:38 AM
^nope

LowSantorin
03-30-2009, 11:03 PM
I figured out what the problem was. Two different continental TB made horrible whining even with all new other TB parts, Put a dayco belt on and it whined for a total of maybe 10-15 seconds then smooth as can be. Finally, 3 tbs 3 exhaustde lifters later