So I was driving the other day and I noticed my truck was smoking out the exhaust really bad. When I would stop at a light it wouldn't smoke too bad but then when I would accelerate I would smoke really bad for a couple hundred feet and then it would let up. The smoke has a blue tint to it.

I got home and started checking things out. Pulled the air intake off and saw a bunch of oil in the throttle body. Thought it could be a bad PCV valve, but put a new one on and still got the same problem.

Did a compression test. All cylinders are between 175 and 180 PSI.
Changed oil it looks fine.
Radiator level has stayed the same during this time.

Any ideas of what to do next, check next?

The truck is a 1999 4x4 v6 5vz-fe with 155000 miles.

 

catch can bro, all the imports have them. lulz
but seriously... what weight are you running?

 

Try pulling a vacuum line from the idle valve on your power steering pump and see if it's leaking. When the valve inside fails it lets the power steering fluid right up into the intake. Had this happen on one of my LS400's.

 

I'm running 10w30 same weight I've been running for years

 

Subscribed, as I have some oil in the intake manifold as well along with before the TB and would be interested to see what the prognosis is.

 

Change the PCV first. Use OEM. #12204-62010.

If you are seeing blue smoke, more that likely the valve guide seals have bought the farm and blowby is occurring.

Install a catch can between the PCV and the manifold to catch the oil and switch to a high mileage oil such as Maxlife or Mobil Super High Mileage until the old ones can be removed and the new ones installed.

 

If the valve guide seals were the issue would'nt there have been evidence of the with the compression test, or would I have to do a leak down test to know that for sure?

 

Not on the compression, which only checks bad rings, which you don't have.

When you changed the PCV valve was the inside of the hose from the valve to the manifold wet with oil?

The seals harden with time, and the only real cure to the fix is to replace them.

Any oil consumption (loss of oil on the dipstick) over time?

 

No it doesn't seem like the oil is in the hose that goes from the PCV valve to the manifold. I spliced a clear piece of hose into that line and ran the truck for 15 minutes to see if thats where the oil was coming from. It doesn't look like it coming from there. I think the oil is coming from the vacuum line that plugs into the bottom of the Throttle Body. I loose about one quart of oil for every 5000 miles.

 

If your compression is good, I would imagine the next thing to look for is leaky valve guide seals like the others mention. Could pull off the intake plenum and look for leaks.

 

If no oil in the old hose from the PCV, then check the hose coming from the back of the driver's side valve cover gasket that ultimately attaches to the intake tube, right before the throttle body. Any oil in the intake?

The two hoses that go underneath the TB to the IAC carry coolant to the latter.

 

So took off the passenger side valve cover today and couldn't see the drain holes on top of the head to inspect if they were clogged or not. Did some more investigating and I think I discovered where the oil is coming from. On the bottom of the throttle body there are 3 places to plug in hoses. 2 of them mirror each other and are on the front and back. These 2 are for coolant. The third is on the very bottom of the throttle body, I think its a vacuum line of sorts. Well that one is where the oil is coming from. I hooked up a clear piece of hose to that line and can see the oil flowing through it. I cant really tell where that line comes from with the intake plenum on there so I'm going to take that off in the next day or two and go from there.

 

Gotta say, if your oil consumption is only a quart in 5000 miles, what you got here is a non-problem.

 

That's your air assist hose for the IAC valve.

It tees in to the main vacuum line that is covered with a piece of trim. That tee is right at the level of your valve cover gasket. Hard to see it and get to it. You may be on to something with the oil pooling from restrictions in the return drains.

 

Yeah Im pretty sure the oil is pooling up in the passenger side valve cover. Any one know where on the head are the oil drain holes? I couldn't find them when I had the valve cover off. Really don't want to pull the cams to get to them.