2011 Jetta TDI cold start noise

When I was a kid, I used a clothes pin to clip a playing card to my bike so it made a great click-click-click os the spokes as I pedaled. That was the last time I heard that sounds until now with my 2011 Jetta TDI on cold starts. Now it isn’t so lovely a sound.

The dealer mechanics initially said they couldn’t hear anything. When I pressed that I heard it every start, they said the noise I was hearing was the combustion in the cylinder on compression and perfectly normal. When I asked whyI didn’t hear the same noise with the loaner car (2013 Jetta TDI I forced them to give me when they tried to split hairs with me on the difference between ‘service’ and ‘repair’), their answer was: “It is a different car.”

HELP - my warranty runs out in a few months and I have visions of the dealer “suddenly discovering” lots of issues upon expiration. Yes, I am a female mostly auto-engine challenged; and, no, I didn’t bring baked goods.

Thank you.

Lisbeth (who really has had the name long before the Girl With TH
he Dragon Tattoo)

That Lisbeth of the Dragon Tatoo is one tough cookie. You may have to emulate her personality a bit to get to the bottom of this noise problem you have.

So this occurs only during the cranking phase? Without hearing the actual sound and where exactly it originates, could be a lot of things, hard to say. But it would probably be worth at least asking your mechanic to check the starter and flywheel teeth for abnormal wear, and the timing belt/timing chain. Accessories (AC compressor, alternator, water pump, etc) and their drive belts could make this kind of noise too.

Thank you - I will ask those things specifically. The noise starts at cold start and continues up to about 30MPH. Might continue after that and maybe I just don’t hear it. I noticed my car idles lower speed than the loaner. And my tac runs higher levels on lower speeds than the loaner.

It could be a noisy hydraulic valve lifter that quiets down after the engine warms. This may not happen at every cold start because when the engine is stopped with that particular lifter over a valve that is by chance closed, the valve spring then exerts no valve spring pressure on the lifter to try to collapse it from which the lifter may not quickly recover and fill again with oil at the next engine start. Yes, you said “every start”. If this is an accurate description of what you are hearing, then you can relay the information to your dealer to see what he can do for you.

I have an old Buick (not VW I realize) shop manual that says to not judge hydraulic valve train noise until after the engine warms. That is not an ideal situation but is one that can be lived with. Don’t tell your dealer that as he may use it as an excuse to do nothing.

These are difficult to find as each lifter must be removed for a leakdown test which a mechanic with the test specification and the correct equipment can do. Another option is to replace every lifter to include the defective one.

Are you aware of TDIClub.com?

Thank you for the thoughts. Everything helps if I have something specific to ask the dealer to check. I recently heard about the TDIClub.com and will check that out s another place for advice.

If the noise occurs at 30 mph, then it isn’t a cranking noise. So no need to check the flywheel teeth and starter motor. But the timing belt and accessories and belts remain a suspect. I concur w/the post above that a hydraulic lifter could be the cause too. I don’t know if your car uses hydraulic lifters though. Not every car does. You might do a little Googling to see if you can find out. Best of luck.