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View Full Version : Help identify noise (VIDEO INCLUDED)



superman_006
05-30-2010, 09:52 AM
Sounds like its in the top end.... it sound like its a random knock. It started doing this yesterday. its like (tick....tick....tickt.tick................tick ....tick)


Its and AEB and isnt throwing any codes

http://i130.photobucket.com/albums/p276/superman_006/th_Video_053010_001.jpg (http://s130.photobucket.com/albums/p276/superman_006/?action=view&current=Video_053010_001.flv)

A4Rob
05-30-2010, 10:18 AM
The sound was kinda hard to hear in the video. My guess would be cam chain tensioner.

walky_talky20
05-30-2010, 10:42 AM
I'd say cam chain tensioner as well. Audio quality is pretty poor though. It be best if you can get us some video from a real camera. Usually the CCT noise is a bit more constant, not so sporadic.

Is the noise coming from the front of the engine or the rear? You can use a screwdriver as a stethoscope to try and locate the source of the noise. If it comes from the lobe on the back of the valve cover, that's the CCT. If it is from the front of the engine, it could be noise from a loose timing belt (failed hydraulic tensioner!) or from the accessory belt. For the last one you can remove (or just take the tension off) the belt to see if the noise stops.

superman_006
05-30-2010, 10:59 AM
Ok.... here is another video in a with better sound (I hope)

It sounds simular to a rod knocking every once in a while... but it sounds like the rear

http://i130.photobucket.com/albums/p276/superman_006/th_S6300007.jpg (http://s130.photobucket.com/albums/p276/superman_006/?action=view&current=S6300007.flv)

bw86
05-30-2010, 02:22 PM
as stated above, sounds like a cct

superman_006
05-30-2010, 08:26 PM
OK... so as soon as I take the valve cover off...The chain should have slack in it?

walky_talky20
05-30-2010, 11:21 PM
No, not really. Even when they are bad, they look fine. If it makes noise, then you change it. Visual inspection won't show you much, unless the plastic guides are broken or severely worn, which is rare but has happened.

You *may* have telltale signs of scratches from the chain on the inside of the valve cover or on the head surface (which you can't really see until you remove the tensioner).

Here is a pic of my head after removing my CCT. Chain was making a bad scratching sound under light acceleration, and a bit of clanking. Do note, my car has the VVT tensioner, so chain slack is sometimes moved from the top to the bottom. It was that feature which was malfunctioning somehow:

http://farm4.static.flickr.com/3070/3722288960_ef6c63a530_o_d.jpg

superman_006
05-31-2010, 06:48 AM
Is it possible to only pull the intake cam on the AEB and roll it out as u bring the tensioner up?

superman_006
06-01-2010, 07:00 PM
I got the valve cover off.... i cant push the top of the tensioner in by hand, and the chain feels tight. I also tried to turn the intake cam so the slack would be at the top but that didnt do much eather.

Is pulling the tensioner out the only way to check the lower for chain travel?

This car also had sevral miss fire codes stored

walky_talky20
06-01-2010, 08:00 PM
Pushing the tensioner by hand is normal. Without oil pressure, it isn't too hard to compress. I don't think an AEB or ATW could have problems with the chain hitting the head (on the bottom side). This is because all chain slack is always kept at the top. On an AWM, the VVT will move the slack to the bottom under certain conditions.

You can remove/change the tensioner just by pulling the intake cam. You may have to remove the rear-most cam bearing cap on the exhaust cam, though. I know this is required for the VVT tenisioner for clearance when "swinging" it up and out. I believe the non-VVT tensioner is the same size in that particular dimension. If you want to pull it and inspect, make sure you paint mark the chain and cams so you can't alter the timing when you reassemble. I would also recommend turning the engine to TDC, so you have the cam marks to double check (16 links between the marks, etc).

After listening to your second video, I'm not sure if I'm convinced it's the CCT. That would be an pretty easy fix, but it kind of sounds like something more serious. It is really hard to judge from just a video. Have you checked the turbo wastegate to see if there's any rattle there? Did you do any stethoscope-ing to pinpoint the source of the noise?

superman_006
06-02-2010, 07:09 AM
it sounded like the rear of the motor... What if I hooked the coils back up with out the valve cover being on it and started it. If the tensioner is bad would I see the chain flopping around on the top side?

superman_006
06-05-2010, 08:05 AM
well i put a new timing chain tensioner in it... its still making the noise. however #4 cylender is completly dead

I checked the coil and even moved it, I know its fireing becasue i grounded the plug on the motor and watched it spark.

I pulled the injuector rail out and all four injectors are spraying and the injector Orings look good and was even hanging on #4 when I pulled the injectors out

I ran a compression test on #4 and it had 185psi... however quite a bit of smoke came out of the spark plug hole when i took the plug out.

aaronamerica
07-20-2010, 12:32 AM
any updates on this. i kinda have a similar situation