lamb03

My 90 ls400 has about 300k miles, a week or two ago i took it drifting on the icy roads and kept it in low gear or 2nd and the only thing i think could have gone wrong was my rpm’s got a bit too high and could have damaged something? When i noticed the noise i pulled over to check my fluid levels and everything was perfect. The noise goes away around 3-4k rpm’s or when i’m cruising

Heres a video (not sure how to post one here)the noise sounds like it’s coming from the middle of the engine

https://youtube.com/shorts/3uXiHGlXTP4?feature=share

aptoslexus

Sounds like something is loose in the belt area.

CLLEXUSS

Hard to say, i've heard bad exhaust manifold gasket sound like that, if you out drifting it it's going to stress stuff that is over 30 years old I imagine

lamb03

i thought it was something loose too but i pulled off some covers and checked but the sound seems like it’s coming from the center of the engine, it’s been driving just fine but that noise is annoying

LeX2K

Sounds like rod knock, stop running the engine. Might be able to salvage by replacing just the rod and main bearings.

It is possible could be a valve lash issue.

lamb03

ye if it’s rod knock this car might go in the garbage lol i guess im just gonna keep driving and find out, i don’t know where i heard these cars were reliable from but that’s a lie ive put 10x the amount of work into this lexus than my other old toyota and it’s still an unreliable piece of junk

paulo57509

That sounds like an exhaust leak or high tension (voltage) that's grounding instead of traveling to the plugs. If it's a rod knock, the sound frequency would be much lower.