Once a day noise

I have a 1996 Volvo 850 turbo wagon. In the last few days, it has started to make a noise when first started, but not any time after that. It runs fine, and starting it later in the day, no noise. The noise is definitely from the engine compartment, and it sounds like some loose piece of metal rattling around inside something that is enclosed. It lasts for about 5-10 seconds, then stops.

I would suspect a loose heat shield.

A loose heat shield would also be the first possibility that I would check. A loose heat shield is not dangerous, but it sure can be annoying. Since it is not dangerous, you can defer repair until the next time that the car is serviced.

Agree with previous posts to a point. Noise from a loose heat shield wouldn’t typically be confined to a cold start, though. Understand that components expand when hot, so it’s possible.

The possibility of a stuck lifter cannot be excluded.

Loose Heat Shield??

Why wouldn’t the heat shield STOP rattling AFTER 15 seconds.

Without hearing the noise…I suspect valve clatter. It needs to be checked out.

Catalyst Breaking Loose In Convertor? Baffle Breaking Loose In Muffler Or Resonator?

Try kicking the tailpipe from the side, several quick kicks (get it shaking),when it’s cold. See if it rattles. If it rattles, then the problem is probably related to the exhaust system heat shields, convertor, what have you. Heat may expand metal and stop rattle.

And here is the answer. Took it in to an independent Volvo mechanic, who luckily had “gone to school” on a very similar case, so was able to pin this down quickly. He said there is a small gear head that protrudes from the end of the starter motor when it is turning the engine over, and there is a spring-loaded lever that retracts the gear head once the engine has fired. In my case, the spring went bad, and the gear head was not retracting, but still rattling against the flywheel. Didn’t know why it did this only on first start, but told us when he was checking it out, it began doing it on every start, and staying engaged for a long time, so guess we got that fixed just in time. Thanks for all the ideas!