Smoke On Startup (looks Blue)

[90LS400Lexus]

UPDATE - yes, it was the idle-up valve... had it blocked and smoking stopped. More serious issues now though, as the steering is hard to turn.

I know my PS pump leaks and that the white smoke on initial startup is because of that, but only recently when I first start my LS400, I am getting an embarrasing imitial cloud of smoke, especially when I leave work in the late afternoons. Its only comes out when first started and gone within 5 seconds, but its embarrasing. I have not been able to smell it yet, but it looks to be very light blue in color, but my car has a relatively low (for Lexus) 220K miles on it and seems like its too early for this to be happening (bad valve seals) on this car. The oil has been changed religiously since new and the oil always still looks almost new at the 3K mile interval when I change it and its always on the full mark. I have had other cars with alot more miles than this that didnt smoke on startup, so I am a little discouraged. If it was valve seals I would think I would have noticed it gradually coming on, but its started suddenly- like over the past week.

Is it possible that the smoke could still be from the PS pump leaking and it just has a blue tinge to it? Or is it time to sell this car?

[smooth1]

I know my PS pump leaks and that the white smoke on initial startup is because of that, but only recently when I first start my LS400, I am getting an embarrasing imitial cloud of smoke, especially when I leave work in the late afternoons. Its only comes out when first started and gone within 5 seconds, but its embarrasing. I have not been able to smell it yet, but it looks to be very light blue in color, but my car has a relatively low (for Lexus) 220K miles on it and seems like its too early for this to be happening (bad valve seals) on this car. The oil has been changed religiously since new and the oil always still looks almost new at the 3K mile interval when I change it and its always on the full mark. I have had other cars with alot more miles than this that didnt smoke on startup, so I am a little discouraged. If it was valve seals I would think I would have noticed it gradually coming on, but its started suddenly- like over the past week.

Is it possible that the smoke could still be from the PS pump leaking and it just has a blue tinge to it? Or is it time to sell this car?

It's a 1990? Yeah, it could just be the PS. When the car first starts up, it's in an open loop mode. (Kind of like an automatic choke.) So it's a bit richer until all sensors get up to temp. The PS might be causing a small amount to pool and hence your getting some smoke. Just fix the PS and it should go away.

[AzHotLS]

It's the Idle Air Control Valve (IACV). Clean it, replace it or remove/plug it. Do a search to find theads discussing each option. I went the replace route on my 90.

[90LS400Lexus]

Thanks!

It's a 1990?

Its a 1991.

It's the Idle Air Control Valve (IACV). Clean it, replace it or remove/plug it. Do a search to find theads discussing each option. I went the replace route on my 90.

Thanks... I will look into that.

[90LS400Lexus]

Thanks. For some reason I cant get the search engine on here to work... can anyone steer me the right direction to replace/clean the Idle Air Control Valve?

Is this the same piece of crap that causes the power steering fluid to get pulled into the engine?

[curiousB]

If you are not burning oil in the engine then its PS fluid getting into the intake via the vacuum hose and the valve in the PS pump. As a test you could just pinch the hose closed for a week or two with a small clamp or vice grip plier's. Alternatively a gold tee may plug the hose (plug the vacuum side so you don't introduce a leak to intake or you'll create other problems.

If after a few days you find smoke is gone then you know to change the valve in the PS pump of to get a new pump. It might now work right away as there is probably a good amount of PS fluid residue in the intake hoses and throttle body that needs to burn off.

[AzHotLS]

This thread is a good read:

http://us.lexusownersclub.com/forums/index...?showtopic=6583

I did a "+valve +fluid +filter +hose" search to find it.