What is this nasty sound?

[DavePolyakov]

1990 740 b230ft. The noises occurred immediately after startup when getting gas. The loud whirring and the clicking sound began at the same time. When I turned off the car there was a whirring sound for 5 seconds after the engine shut off. I went home right away took this video and turned off the car. I recently did an IPD turbo cam swap (only 10 miles ago) maybe I forgot to torque a bearing cap? I doubt it but I have no idea, it never made this sound before and was fine before getting it gas. The oil level is fine. Please help my noobiness. Thanks

https://www.youtube.com/watch?v=Uax99WeCpi8

[Jack]

Turbo or your ****ed something with timing belt

Isolate where the sound it coming from because it’s hard to tell without being there

[DavePolyakov]

I hate and love your comment because I now think it's the turbo.

The timing belt was done correctly, I've done it multiple times and it's still in the correct position after verifying. The sound is coming from around the head. Could definitely be from the turbo.

The turbo came with a 240 I bought in unknown condition, I've driven 100 miles with it. Before this, there was an occasional "siren" sound at lower speeds. I googled "bad turbo" the first result is a whining sound and whirring, or siren. I forgot to mention I did smell some oil/burning smells on the ride home but not super intense. No smoke from the exhaust looking in the rearview mirror. I'll pull off the intake boot and check shaft play.

When I installed it I forgot to prime it with oil. Was this my crucial mistake? It's a 15g. I literally only drove it 100 miles and only got into boost less than five times as I am breaking in a new clutch.

Originally Posted by Jack

Turbo or your ****ed something with timing belt

Isolate where the sound it coming from because it’s hard to tell without being there

[Jack]

Take intake boot off and see if the turbine is rubbing/ lots of play

[DavePolyakov]

I started it up and went for a drive about 30 minutes after I took the video. The sound was completely gone, didn't come back after turning off and restarting a couple of times on a 10-minute drive.

[Mr. V]

Sounds to me like it's not an engine noise, more of an accessory noise.

Bearing going bad in AC, alt or PS perhaps?

[DavePolyakov]

Not sure but I think it may be my timing idler pulley? Or the alt bearing as well. There is no ac. I will try to find an idler pulley and see if that fixes it.