First off, hi, guys! I know it's been awhile. All the advice you gave me before on my 86 pickup worked. Finally got it running great although it recently blew a head gasket. I'll have to fix that next.

For now, though, here's the problem. My 4-runner got to a point where it wouldn't start. I had replaced the muffler last year because it wound up blowing up (with an incredible boom). It bellows out thick white smoke when it does get started. I tried using starting fluid, spraying some into the intake until it finally started but the smoke was thick and it cut off. Didn't want to start back.

I did the diagnostic thing, and it registered code 24 (mass air flow sensor). I got a refurbished one online and it's at least starting. But there was oil going everywhere and running down the exhaust (where the main line connects). Online diagnosis said it could be valve cover gasket. Replaced it (even though I really doubt it was the problem - it looked good). Got it started. Still leaking all over exhaust. Removed pipe and replaced circular gasket (the new one looks like a metal casing with a black fibery material filling the inside of it) and bolted it back. Got it started again. Noticed oil leaking and found it was running down the intake hose, running through the MAF sensor and out the breather. Did the diagnostic thing again - still 24. Figured that's because it's full of oil. Took it off to drain.

Searched online for info on oil in the intake and now they're saying it could be the PCV valve. Got another one of those and am reading about how hard it is to replace. Before I go though all of this trouble can any of YOU guys help diagnose the problem? I'm hoping it's not the PCV valve, especially considering it's on the passenger side and all the oil is coming from the driver's side. Am I overlooking something? I'm sure everyone here has more experience with these things than I ever will, so any and all advice will be greatly appreciated! Thanks everyone!

 

the only thing i can think of that would cause that is unburned fuel igniting in the exhaust pipe?? bizarre.

in general, smoke colors are: oil is blue, gas is black, white is water.

what intake hose? coming from the valve cover to the plenum? what engine? 22re or 3.0??

how would oil get from the engine up into the airbox? or is it a hose going into the later model 22re plastic air intake? i don't have that on my '86.

pcv valve should be a piece of cake, where did you read that it was difficult? the biggest issue there is the pcv gasket getting hard, loosing pliability.

the fact that there was a lot of white smoke earlier would make me question the condition of the head gasket.

 

The smoke is definitely more white than blue... There's also a big black spot on the ground where it blows (oil?) out of the tailpipe...

Didn't really mean hose. That's what I found it listed as on ebay: "Engine Throttle Body Air Intake Hose". It's more like an angled boot with an L-shaped spout coming out of it that connects a hose between it and a spout coming out from on top of the valve cover. The boot connects the intake at the throttle body to the tube that connects to the mass air flow sensor. It's a 3.0. Really wish it was a 22re, however, because that would have been much simpler to fix!

I think oil is coming through the throttle body and then running down through the air intake. I don't have the OEM plastic box. Mine's modified. This isn't mine, but this looks almost identical to my setup:
It's leaking all the way down through the air filter in the bottom.

Everywhere says it's difficult (on a 3.0 anyway!)... unless you use long angled needle-nosed pliers or tilt the plenum out of the way to access the valve cover easier (it's on the passenger side, buried under everything). Don't know if that's the cause of my worries, though, and I'd hate to go through all that trouble if it's something else...

There's no water in the oil, however. And it doesn't seem to be losing coolant (mostly water I'm sure). So I'm not sure if it's the head gasket or not! I really wish I knew more about mechanics! I sure hope this info helps out! Thanks again!

 

does the black spot on the ground dry up, without leaving any residue? maybe stick something in the path of the exhaust, then see if it looks or smells like oil?

pcv is pretty accessible on the 22re, but i've never worked on a 3.0.

that's good news about the no water in the oil, and no coolant loss... check for mayonnaise under the radiator cap, and inside of the radiator overflow.

there is also a block check kit that's supposed to be able to detect engine exhaust in the radiator, but i've never used it.

maybe one of the 3.0 people will weigh in with some ideas.

 

I think it's definitely oil. It's almost a permanent black spot. It's rained and rained and rained but the spot is still there (it's mostly on grass - the parts on dirt washed away).

Both look normal.

I sure hope so! Thanks osv.

 

I had white smoke coming out of my 98 4runner on start up. The coolant level never went down (I drove from Miami to NYC) but the engine oil level would diminish. Had to top up three quarts intermittently through the 2000mile drive. Just to say that white smoke and all the signs of a HG leak may not actually be that, if my runner is the only proof of it.