Odd Noise From Engine Bay During Startup - NOT Header Tick (1 Viewer)

[TheForger]

2000 LC with 216k and no issues at all. I've recently noticed during cold starts there is an odd noise that comes from somewhere in the engine bay; I'm thinking the brake booster area. The truck starts and runs just fine, and about 2 seconds after starting, the noise begins and lasts for about 4 seconds before going away and never coming back until the next cold start (usually the next morning). I don't have enough time to run around to the engine bay after starting it to see exactly where it originates from because it goes away too quickly. I may get someone to start it for me while I look in the bay next time. It sounds like a pump whining and nearing the end of it's life span so that's what makes me think booster but that's just a guess. Like I said engine runs perfectly and also no codes on the Scangauge. Only occurs at the beginning of a cold start and does not occur during any other startups or while driving once the engine has warmed up. Seems to only happen if the ambient air temp is below ~40℉. Honestly I'm not too worried about it right now since like I said everything runs perfectly, but if it is in fact the booster assembly I may start considering a reman unit since AFAIK it has never been replaced at 216k miles. Fluid looks clean, has appropriate amount, and doesn't smell burned. Any help or advice would be muy apreciado! Yes I did some searching first but didn't find anything similar to what I'm experiencing, only the classic header tick and a knocking sound. I managed to get a video this morning when it was 31℉ and linked it below:

 

[2001LC]

Not heard that before!

You only need turn key to on, and booster pump will start. So next cold start run booster before starting.
Also, your brake reservoir look like fluid was at max line. It should be below max after booster pump runs.

This may be issue with a valve of charcoal canister or it's associated valves.

 

[FxFormat]

It almost sounds like a power steering pump whine

 

[2001LC]

It almost sounds like a power steering pump whine

Now that you mention it, kind of like air in PS pump.

 

[Austin Hot Shoe]

Funny this pops up today, I have that ticking noise in same conditions as you......my thought was more of a lifter issue....thoughts? EDIT, just listened to video, not the same.....do you guys have the lifter tick, not manifold.

 

[Njck22]

I recognize this sound from another 100 series video 20 secs in

same sound, same length. Could be an electronic valve actuating?

 

[aljordan]

Power steering pump whine is what it is. Mine does it when it's sub 35°F for about the same amount of time. There is a (likely) a screen in the PS reservoir at the outlet that restricts the flow of the cold fluid into the pump and the pump doesn't like that very much. The supra folks will back flush the reservoir and add fresh fluid to resolve it.

Next time it happens, turn the wheel to see if it goes away or gets louder. That would remove any doubt that it something other than steering related.

 

[2001LC]

Take your drive belt off before next cold start. This will eliminate PS pump, A/C, fan bracket, fan clutch, alternator, and both idlers.

 

[geanes]

Sounds like a PS pump to me.