Can bad serpentine belt cause engine vibration?

skgwilliams

Veteran Member
Joined
Oct 11, 2005
Location
near Boston
TDI
Jetta, 2001, auto, 144,000 mi, black
Hi everyone,

If I am in the wrong forum, I apologize. I'm a relative newbie so I wasn't sure if I have an A4, but I thought do so I figured this was a better place to post than 101.

My car is a 2001 Jetta TDI. Automatic with 109,000 miles.

Here's the situation. Since Monday of this week, my car has sounded much louder at idle when in drive. I popped the hood with the engine running and in park and looked around. The noise & vibration level don't change based on engine temp or driving speed.

The whole engine is vibrating more than I recall it doing before. And is much louder. Not deafeningly louder, but more noise than normal. It basicall sounds like it usually does but with the volume turned up.

With the engine off I looked at the serpentine belt because to my untrained ear that is where it sounds like the elevated noise could be coming from.

The serp belt is textured on the back. Now keep in mind I didn't remove the belt, but the left side is smooth on the back and the right side is textured on the back. If I had my camera with me I'd take a picture to show.

It that an unusual wear pattern? Is this probably unrelated to the increase in noise.

Background: Intake was cleaned and timing belt changed about 10,000 miles ago. Fuel filter changed too.

I hadn't filledup with new fuel. This is the same fuel I was running prior to the noise increase.

Any ideas would be appreciated to help troubleshoot, if this is in fact a sign of trouble.

Thanks for reading my post :) ,

skg
 

dieseldorf

Top Post Dawg
Joined
Oct 11, 2000
Location
MA
TDI
ex- 1996 wagon, ex-2000 Jetta
do you know if a qualified individual changed the TB? I hope you are not on the verge of catastrohpy, skg.
 

skgwilliams

Veteran Member
Joined
Oct 11, 2005
Location
near Boston
TDI
Jetta, 2001, auto, 144,000 mi, black
dieseldorf said:
do you know if a qualified individual changed the TB? I hope you are not on the verge of catastrohpy, skg.
Is that what you think this is? Timing Belt problems?

It was a reputable shop, with limited TDI experience. They service mainly high-end foreign cars. Mine isn't the only TDI they've worked on, but they've only serviced a few.
 
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jasonTDI

TDI GURU Vendor , w/Business number
Joined
Apr 26, 2001
Location
Oregon, WI
TDI
20' RAM 3500 CCLB dually HO/Aisan. 2019 Cherokee 2.0T
Could be a bad tensioner for the serp belt or the roller. Oil leaking from the tensioner? Is it excessivly hot after driving? The wear pattern is normal, I see it a lot.
 

skgwilliams

Veteran Member
Joined
Oct 11, 2005
Location
near Boston
TDI
Jetta, 2001, auto, 144,000 mi, black
BobnOH said:
engine vibration? maybe motor mount?
After all I read about motor mounts failing, I was thinking that could be the problem. Are the mounts visable from the top side or do I have to get the car up on ramps or a lift for a good view?

I'll find a way to check that.

I owned a Saturn prior to this car and with much lower milage on the car one of the engine mounts cracked and had to be replaced.

Thanks.

-skg
 

jasonTDI

TDI GURU Vendor , w/Business number
Joined
Apr 26, 2001
Location
Oregon, WI
TDI
20' RAM 3500 CCLB dually HO/Aisan. 2019 Cherokee 2.0T
These mounts just don't fail. The bolts do.
 

skgwilliams

Veteran Member
Joined
Oct 11, 2005
Location
near Boston
TDI
Jetta, 2001, auto, 144,000 mi, black
jasonTDI said:
These mounts just don't fail. The bolts do.
Thanks Jason. I'll find a way to check that. And thank you for the advice on the serpentine belt wear pattern.

I'll be sure to check for the things you mentioned, heat, oil leakage.

-skg
 

dieseldorf

Top Post Dawg
Joined
Oct 11, 2000
Location
MA
TDI
ex- 1996 wagon, ex-2000 Jetta
skgwilliams said:
They service mainly high-end foreign cars.

S, that becomes somewhat irrelevant as many others have had the mis-fortune of discovering. When it comes to the timing belt changeout, many are beffuddled.

You may want to have Chris Hill in Braintree take a quik look - - it the bolts break, you have a big repair ahead!
 

skgwilliams

Veteran Member
Joined
Oct 11, 2005
Location
near Boston
TDI
Jetta, 2001, auto, 144,000 mi, black
Well 2+ years and 40,000 miles later I remembered posting this thread. I thought I'd come back and update.

Nothing catastrophic happened. I kind of got used to the vibration. :D I knowin retrospect I probably should have had it looked at but I didn't.

When I started this thread 2 years ago I had just had a 40k timing belt and related parts installed at the time of the change.

2 years later it was time for the belt change again and I just had it done again last week but this time by mrchill. Got the 100k kit this time During the change he recommended replacing one of the engine mounts that looked questionable.

Well that engine mount replacement has made a noticeable difference in the feel of my car. It no longer vibrates the same way it did before when stopped in drive.

This is a great community and I wanted to contribute by adding a conclusion to my thread, even it if is 2 years later. :D
 
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