I had a strange problem (aren't they all) with my 92 4Runner which I
couldn't find any answers for on the internet so I am posting this in
the hopes that it'll help someone else with the same problem. (Cliffs
at the bottom).
The power steering pump in my 92 4Runner had been leaking for a while,
but it was minor so we just kept filling it up every few weeks when it
started to whine. Eventually the truck would let out a big puff of
white smoke on startup, but only randomly. Sometimes it would not do
it for weeks. I could not fathom how these two could be related.
The smoke worried me so I took it to the dealership and also to a
private mechanic and they both told me that the engine was shot. I
mentioned the power steering problem but they did not think the two
were related. They gave me theroies about how it was burning oil,
like depending on what position the valves in the engine came to rest
in it would sometimes let oil drip into the cylinder which would then
come out as smoke when you started it up.
The worst time was after a movie at the theater, it nearly filled the
entire parking lot with a cloud of white smoke.
Eventually the power steering leaked so bad that I stopped filling it
up. I wasn't about to fix the pump then because it was winter and I
don't have a garage.
Magically the truck stopped smoking on startup and all was good.
Now summer came around and it was time to change the power steering
pump. I took it all apart and noticed two vacuum lines coming off of
a valve on the pump. When I took them off power steering fluid came
It turns out that this valve is there to adjust the engine when you
are turning and the engine is at idle. It had failed and was
basically letting power steering fluid enter the engine. I replaced
this valve (which cost $140CDN at the dealership, couldn't get it
anywhere else) and it no longer smokes.
1. 92 4Runner 325,000km white smoke at startup (intermittent)
2. Mechanics say engine is shot
3. Due to power steering pump failure, notice that truck doesn't smoke
when there is no power steering fluid
4. Replaced pump and valve that comes out of rear left bottom of pump
(when looking at the front). It has 2 vacuum lines coming out of it.
5. Problem solved!