Scary noise on cold start

[Youx]

Hello,

I’m slightly worried, as I just got a very strange noise.

I started my 86 (1 week since last use) inside my garage (temperatures are pretty high for winter, 15°C/59°F).

Motor revs to 1500, as usual, then I get a loud sound « ta-ta-ta-ta-ta-ta-ta ». Kind of like firecrackers, or when your exhaust has holes, but I’d say higher pitched. A bit metallic, but maybe that’s my mind. And definitely loud enough to be heard over the motor, with doors and windows closed.

Anyway, it lasted maybe a 5 seconds, while I was WTF-ing, then it disappeared, RPM revved down to 1000, and I did not hear it anymore as I went shopping.

How worried should I be?

Edit: car is 2012, stock, and I pressed the clutch pedal during the sound and it did not seem to affect it.

[blsfrs]

What is the mileage (kilometerage?) on your engine? A video with sound would be helpful.

[Youx]

~82000km. The recall was done last December.

I’ll try to start it every few days, with a phone ready to record, in case it repeats.

[TommyW]

What oil are you using

[blsfrs]

First guess would be a rod knocking until the oil pressure built up but your engine mileage is rather low for that.

[Youx]

Originally Posted by TommyW

What oil are you using

The one that Toyota puts in at maintenance, so 0w20 iirc?

[TommyW]

Originally Posted by Youx

The one that Toyota puts in at maintenance, so 0w20 iirc?

Hmmm yeah plenty thin. You had the recall done and that's a red flag. If they let silicon get in the engine it may be clogging things up and compromising the oil flow. Keep an eye on it. Not much you can do if that's the case. Yes try starting it often to keep a film of oil on the bearings

[Yoshoobaroo]

If it keeps doing it, try priming the oil pressure when starting it cold. You do this by holding the gas pedal down when starting the car. It will crank, but not start until you take your foot off the gas. Let it crank ~3-5 seconds to let the oil pressure build up, then let it start.

[Ultramaroon]

Originally Posted by Youx

~82000km. The recall was done last December.

I’ll try to start it every few days, with a phone ready to record, in case it repeats.

Will check back for the recorded sound.

[humfrz]

Originally Posted by Ultramaroon

Will check back for the recorded sound.

What part of « ta-ta-ta-ta-ta-ta-ta »,, don't you understand?

[wbradley]

Maybe a piece of the cat honeycomb broke loose

[Ultramaroon]

Originally Posted by humfrz

What part of « ta-ta-ta-ta-ta-ta-ta »,, don't you understand?

At this point, all I have is the mental picture of a man saying it with a French accent.

[Sapphireho]

.

[JohnH]

Originally Posted by humfrz

What part of « ta-ta-ta-ta-ta-ta-ta »,, don't you understand?

as a professional wrench, there are at least 5 normal issues that make this kind of noise. Its definitely a relevant thing to want to listen to it.

For example, is it a lifter not pumping up quickly? Or an exhaust manifold leak? Or a heat shield? Or an item stuck in the belt that flung itself out after a bit? All completely different diagnosis and prognosis. All to Tatatatatatata