Mikew06

I recently picked up my first 1998 ls400 with 168k miles after looking for one forever and it’s having a bad problem of white smoke on start up and acceleration, I heard about the PS leak into the engine but the previous owner already capped that valve off along with the where the lines went..there’s no oil or coolant disappearing nor contaminates in it, there’s no milkshake cap and surprisingly the only fluid that’s disappearing is power steering fluid? I drove it 20 min from where I bought it and the whole pump was dry once it got dry I noticed there was a lot less smoke coming out of the exhuast I filled it up a little after that and there was no liquid gushing out from anywhere, I had one CEL for a misfire but that was fixed with a new spark plug other than that it has 0 codes if anyone has any advice on what to do or what to check on this before I just do a head gasket test and compression test it would be greatly appreciated thanks in advance

400fanboy

Just because the previous owner capped a valve doesn't actually mean a PS leak is gone. Yes there can be a leak from the idle up control valve on power steering. Check that no power steering pump fluid in vacuum lines. Is the area around the PS pump or reservoir wet from fluid? A leak strong enough to drain it would leave a lot of evidence.

However - there may be multiple overlapping issues here. What color is the smoke? Is the car burning engine oil?

Mikew06

Yes I agree as well there should be a evidence from the PS leak but I can’t find it anywhere, no oil is burning it stayed the same level and isn’t a weird color, the smoke is white and smells like a normal exhaust to me

400fanboy

Stupid question. I have to mention it - but the LS400 does put out a considerable amount of condensation in the winter compared to other cars I've owned. The exhaust is quite voluminiumious. Perhaps this is more than you're expecting in the cold weather the midwest has at the moment?

Beyond that - going to have to do a lot of testing. If the smoke is coming from something that's burning - so you're going to have to start pulling parts to inspect for failures and\or pooling oil. Inspect spark & injectors, throttle body, etc.

Lots of information already documented about this. Suggest the following google search:

Which provides examples such as:

https://www.clublexus.com/forums/ls-...m-exhaust.html