Engine Noise - Timing Belt???

[burneo1217]

Hi, well I just seafoamed my engine yesterday, and I did it through the vacuum lines. The car was performing extremely good afterwards, but I started it today and I heard a noise similar to tin cans from the head on the engine. I also performed a compression test prior to the seafom process and it came up to 175, 180, 180, 180 which I believe is pretty decent for a car with 120K miles. I opened the timing belt cover (while running) to see if I could hear the noise better and effectively I did. I don't know if the previous owner changed the timing belt, and I'm assuming he did not. Could this be the timing belt? I've tried doing some research and I've come to 2 probable causes. One the timing belt and the other the valve lifters. I'll try to post a video later today if not tomorrow, but while doing my research I've come across this video with a similar noise to mine, but in an S4 http://www.youtube.com/watch?v=bZCdmOEXGHI.
Can anyone help me find out how to tell if the belt is bad? It looks old and rusty and kind of cracking looking on top. Thanks to everyone for your input.

[koolade9]

Hi, well I just seafoamed my engine yesterday, and I did it through the vacuum lines. The car was performing extremely good afterwards, but I started it today and I heard a noise similar to tin cans from the head on the engine. I also performed a compression test prior to the seafom process and it came up to 175, 180, 180, 180 which I believe is pretty decent for a car with 120K miles. I opened the timing belt cover (while running) to see if I could hear the noise better and effectively I did. I don't know if the previous owner changed the timing belt, and I'm assuming he did not. Could this be the timing belt? I've tried doing some research and I've come to 2 probable causes. One the timing belt and the other the valve lifters. I'll try to post a video later today if not tomorrow, but while doing my research I've come across this video with a similar noise to mine, but in an S4 http://www.youtube.com/watch?v=bZCdmOEXGHI.
Can anyone help me find out how to tell if the belt is bad? It looks old and rusty and kind of cracking looking on top. Thanks to everyone for your input.

If you just seafoamed... did you run any through the oil? did you change your oil afterwards? Your noise is most likely the lifters.

However, if you see cracking in your timing belt...get it replaced STAT! If this hasn't been done by 120k, you're driving a ticking timebomb... If it has been done already, let's say at 60k, then it sounds like you're up for the 2nd change anyways...either way...cracks=bad news!

If you're seeing rust on the tensioner pulleys, you could be approaching bearing failure in one of them, which is just as bad as having a timing belt snap...

stop, drop, and

[FourRings80]

If your able to remove the serpertine belt by pulling to tensioner clockwise with a 19mm. You can atleast eliminate half of the sources possible. There's not a lot of room, but worth a shot. If it looks old and bearings look rusted (mostly around the seals) then chances are it's the 60k belt.

picture from yoogene83 timing belt diy:
[IMG][/IMG]

good luck!

[dirtybrd]

To me it sounds as if you have a bearing that has failed, either in the WP, idler, or tensioner. No matter what the niose is, if the belt is cracked you need to replace it ASAP. If the bearing seizes that belt will snap and then you're looking a big $. Honestly, I wouldn't drive it until it's fixed.

[burneo1217]

Thanks to everyone for the replies. I also think is the timing belt, although the noise has stop for now. I took the car for a lap and then back to my garage and the noise was gone. Anyways I'm getting a TB kit, but I also would like to know if I need to buy the hydraulic tensioner. What are the signs of a bad tensioner? I'm not planning on driving the car until I get the new TB. I'm also replacing all the vacuum lines so if anyone has an outline of all of them for a 1.8T AMB engine I would really appreciate it. I would post back here for future reference. Thanks.

[dirtybrd]

Replace everything in there, it's cheap insurance so you don't have to do the job twice.

[FourRings80]

Is this what you're looking for?

[IMG][/IMG]


1-EVAP canister
2-evaporative emission (EVAP) Canister purge valve -N80-
3-non return valve for Evaporative Emission (EVAP) canister purge regulator valve
4-Air cleaner with MAF -G70-
5-turbo charger
6-Combi valve for secondary air injection
7-to brake servo
8-non returne valve
9-suction jet pump
10-non return valve
11-Vacuum reservor
12-secondary air injection (AIR) valve -N112- *under intake manifold*
13-crankcase breather
14- non return valve
15-intercooler with (MAP) air charge pressure sensor -G31-
16-throttl valve control module -J338-
17- recirculating valve for turbocharger -N249-
18-intake manifold
19-vacuum unit for pressure control
20-wastegate bypass regulator valve -N75-
21-mecanical air recirculation valve
22-crankcase breather pressure regulating valve
23-secondary air injection (air) pump motor -V101-

[burneo1217]

Yup exactly what I was looking for. Do you have the outline of the numbers as well? Just to get a better idea where everything is located. Also, dirtybrd thanks for helping a lot the AZ community with your advise... always appreciated. Thanks everyone...

[dirtybrd]

I enjoy helping others, mainly due to being helped by people here. Just passing the torch.