cdm3675

Now at 130k miles. The engine makes a loud tick when cold, then the sound is much less when warmed up. Seems to respond slightly to changing the oil, or adding more oil. I try to keep it full of oil at max capacity without overfilling; adding a little oil attenuates the ticking sound. What's the problem? What to do with it?

Ritz

Have you owned the car since it was new? If so, has it always had regular oil changes with synthetic oil? That sounds like either a failed/failing cam follower or one that is slightly gunked up with oil sludge.

If it's the latter problem, sometimes you can dissolve the poo in the follower with a little solvent in the oil. Some people think this is heresy, but I've done it on some sludged up 1.8T and 2.0T engines with success. Add some Marvel Mystery oil so that it's about 10% of the engine oil volume (that would be about 24 ounces). Drive it around like that for a couple hundred miles then change the oil and filter. If it's a fouled follower, the ticking will go away almost immediately after you add the solvent. MMO is basically just solvent + light oil.

If that doesn't improve things, it's time for your mechanic to do a more thorough diagnosis and find the exact cause of the tap. Hard to diagnose something like this without actually hearing the noise.

Good luck.

Best,

Jack88

I can't help you here, other than to try to further isolate the noise if you can. These things have a tick from the factory new because of the FSI. Is this a separate tick or has the tick of the FSI become exaggerated? If you follow Ritz's advice, make sure you don't put a lot of miles on it that way, just a couple hundred. Going too long with that sort of stuff in your oil will cause damage, but I've never heard of problems if you do exactly as Ritz says. Still, be cautious.

MP4.2+6.0

Need more diagnostics for anything deeper. But for simple DIY to start:

1. Can/bottle of oil cleaner solvent just before next oil change. Usually labeled as something like motor flush in a variety of brands on parts store shelves. Helps dissolve gunk around areas like lifters that can be (most) common noise sources.

2. The light oil type oil additives as mentioned, at least in the smaller quantities the bottle instructions will describe.

3. Techron in gas. Sometimes thought of as "no longer necessary" or doesn't help" with FSI motors, but that is mostly true only about the valve cleaning that applies to port injects motors. It still cleans injectors that themselves can make noise with pulse cycle, may clean combustion chamber a bit, etc.