2002 Acura RSX, K20A3 (base RSX), 162K miles, TCT (timing chain tensioner) replaced twice already, last time about two years ago, significant "messing" with tensioner and timing because I turned the crankshaft too far during replacement.

Lately - with temperatures well into the single digits and when the car has sat for 8 - 12 hours, I get a momentary grinding noise upon cold start.

This noise was completely relieved for 1 month/1K miles with a fresh oil and filter change (Mobil 1 5W20, Mobil 1 filter), so I am convinced it is related to timing chain slack (since the tensioner is oil pressure driven) and not the other common cause of cold-start noise for this engine - starter failure.

The noise is momentary, lasting a few seconds at most. Should I bother to replace the TCT again? I am afraid that without treatment, the patient will jump time and require even more attention/care than a simple TCT replacement.

On the other hand, it is bitterly, bitterly cold here. I don't know if I can do this job myself on account of the weather. Taking it to a shop would not only require more expense, but another opinion, time off from work, etc. etc. etc.

Bottom line - with a few seconds of timing chain slap due to momentarily insufficient oil pressure, how likely is the chain to jump time?

Not too great. Replace the chain and tensioner, once the ambient temperature warms up.

?! Chain too! That's a major operation with this car - requires removing the engine!

Would you consider replacing just the tensioner alone - it's a known weak link on this engine.

Thanks.

If you don't replace the chain, then you need to examine it very carefully. Personally, I would replace it, even if it means lifting the engine. Timing chains stretch (wear) more than many people realize, especially if the oil ever got low (splash lubrication). Since you live up north and have 162,000 miles on it, I would replace it. Were the tensioners OEM parts?

If the chain is worn enough to need replacing, what about the rest of the engine? Is it worth it to replace the chain and keep the car?

So you don't like the (simpler, cheaper) idea of just replacing the tensioner - first - and seeing if the noise resolves?

Yes, both tensioners were OEM.

You've replaced the tensioners twice already, which is unusual. It sounds like something else may be part of the problem. Timing chains are relatively new for Hondas. There have been unexpected consequences of going to chains; i.e. complaints of vibration and wear. Talk to several Honda dealers in your area and see what they suggest.

Thanks. I'll ask.