Hey guys just bought an 01 Ls430 UL and everything interior and exterior is great but it does need a lot of engine work. After buying and driving it for a bit some smoke started coming from the engine bay but couldn’t tell where exactly it was coming from and it also wasn’t overheating at all. Check engine light came on and needs a new thermostat. Could it possibly be that it’s just cause of the thermostat or is it a possible head gasket issue? One thing that I just noticed is that the rim where the radiator cap goes is sorta milky I’ll go ahead and attach a picture. Thanks!

 

Check the valve covers for oil leak

 

If it's not been driven for a while there could be all kinds of debris in the engine bay just waiting to fall onto the headers and make smoke.
As others have said, also look for oil leaks in the engine bay, especially onto the headers.

That grey sludge looks like a water/ATF mix. Do the 01s have the same ATF cooler in the bottom of the rad as the 04-06 have?
If so, I'd consider fitting a new rad as they can leak mixing ATF into the coolant (not good) but more importantly coolant into the ATF (trashed tranny!).

 

What color smoke? Is it wispy like steam or thicker like burning oil? What does the underside of the oil fill cap look like?

 

Yeah I believe they do have the transmission cooler in the bottom just like the 04-06 and the valve cover gaskets looked fine but I’ll double check to see one thing that might be leaking onto the headers is the power steering fluid I seen that the hose is bent pretty bad and might be leaking a bit. As to the smoke it’s just regular white smoke coming from the engine bay doesn’t come from the back end at all

 

I’ll take a picture of the oil cap when I’m off work as it is just sitting right now I don’t wanna damage it by driving more I would say the smoke was wispy not really thick

 

Thanks bigboomer I’m highly considering changing out the radiator now

 

Sorry for the late response haven’t been in town but I’m finally gonna start working on my ls430 here’s the picture of the oil cap for whoever asked

 

Look along the seams of your radiator for signs of leaks. Hard to tell from pics but it looks like the circled area might be suspect. might be time to replace. And that cap looks like it needs to be pitched.