Oil in air intake

Hey, I just purchased a Toyota Tundra 01 v6. It has 160k miles. I replaced the timing belt, water pump, all belts, plugs, ignition wires and alternator. It runs great, however, on start it smokes heavily. It seems to be from the PCV valve. I have replaced it with two different PCV valves(haven’t looked for a OEM one yet) and oil continues to pool in the intake piping. It is excessive to the point of saturating the air filter.

Any suggestions on what to try to pin point the problem? I have a mechanical background so I’m willing to look deeper. Thanks in advance.

 

Paging @Tundra2! A fellow V6 Tundra owner needs your expertise!

 

The only thing I can think of is to try an OEM tube, grommet, and valve.

Here are OEM part numbers from when I did mine.

• 90480-18001 PCV Valve Grommet
• 12204-62010 PCV Valve
• 12261-62041 Hose Ventilation N (hose from PCV to intake.)
• 17176-62040 Plenum Gasket (Intake manifold)
  

 

@Tundra2 is the PCV valve the only possible cause of this issue? Or have you heard of other possibilities? I do think it is the problem due to the clear visible oil on the out side of the PCV valve.

 

I'm not an engine expert by any means, but it could be that your aftermarket PCV Valve is not seating properly in the grommet on the valve cover.

How many miles?

 

@Tundra2 165k, and I agree with that observation. It’s a rubber grommet and the former one was plastic, but I replaced it due to it being cracked. I’ll order the OEM parts and see if it helps.

 

Good deal.

In the mean time, perhaps @empty_lord will be able to help more now.

 

Not optimistic about another PCV or different hoses or grommets improving this condition. The PCV is working as intended.

Excessive oil vapor in the crankcase is caused by the engine's mechanical condition. The PCV is essentially a check valve that allows crankcase vapors to flow one way to the intake for disposal (combustion). A properly functioning PCV wouldn't be the cause for excessive oil vapor.

If the engine wasn't smoking before, it was because the PCV was plugged.

 

Or, You have some engine issues increasing crankcase pressure. Blowby from worn rings, head gasket issues etc. Maybe clogged oil jackets in the head or block from lack of oil changing maintenance or overheating. Something is forcing more oil through your PCV than should be going through there. it's more of an anti-siphon valve to keep air from entering the head and allow excess pressure to be vented into the intake, but very little oil should be entering the valve. Engines used to just have breathers that opened to the atmosphere, but the gases present in there are bad for the ozones, so back into the combustion chamber they went. Second possibility, clogged air filter? The intake could be sucking from your PCV like a milkshake straw.

 

Beat me to it

 

How is the oil getting to the air filter?

 

That makes sense @KNABORES the air filter is saturated so that’s a possibility. I’ll still replace the grommet with OEM because the one I purchased is rubber and almost slipped into the jacket. When I replaced the grommet I did notice excessive amounts of oil “sludge” there it had coagulated. Oil is entering the air filter because of how much oil is getting into the intake and past the carb. Then it leaks down and pulls in the ribs of the piping. I’m guessing it was before I owned it because I clean it daily to prevent extra oil getting to the filter.

 

Sludge is bad. During my valve cover gasket repair I had both of the heads exposed and it was so clean in there you could eat off the valve train assemblies. Shiny even. 225k miles on the motor at the time. Synthetic oil is a thing. And it's good. There's no excuse for having sludge buildup in your motor anymore. The previous owner did not do a great job maintaining that engine sounds like.

 

That oil would have to be leaking in when the vehicle is off to get past the throttle body (no carbs on these bad boys). If it was coming in whole the engine was running, it should get pulled through the throttle body and into the intake manifold, producing that white smoke you are seeing. It should not continue to enter the intake manifold and soak the air filter. None of this sounds normal. Compression test would be a good start.

 

@KNABORES i completely agree, the former owner used conventional and I immediately changed to synthetic. I think I’ll start by disassembling the top end and cleaning out any excess build up or gasket leaks, then I’ll go from there. I’ll keep this thread updated and if anyone has anything I should start with please let me know.

 

@KNABORES I completely forgot that that was the throttle not a carb ahah! I know it’s DI but it slipped my mind. Yeah it’s weird that it’s leaking down into the piping. Any other vacuum hose that could cause such a thing? I did a compression test, all cylinders came back around 145psi-150

 

Not direct injected (booo, bad for valves), but sequential multi-port. You may have to pull the heads to de-sludge them properly. If it's excessive sludge buildup, I would worry about plugging those oil jackets that drain back into the crankcase. Using a high detergent oil to slowly clean that sludge up over time would be a little safer and easier. But your original problem should be diagnosed before I would tear into anything. Short term solution for running the vehicle's sake - install a catch can.

 

@KNABORES sorry if this is a stupid question but, what’s a catch can, and what oil would you recommend? Also, would a leak down test be something I should try to get done? What test/observation will get me closer to solving the problem?

 

A catch can goes in between the PCV and the intake. Its basically a reservoir for the oil that's getting pushed through that valve. You can simply empty the catch can when it gets full and keep that oil out of your intake. The gasses are still able to pass through the catch can and into the intake for combustion.

 

How much oil is in the engine?

 

That Liquid Molly engine cleaner might work. Might be a bit risky.

https://products.liqui-moly.com/pro-line-engine-flush-1.html

 

Could be way to much oil in the engine. I’ve seen that before.

 

Yeah, I'd be leery of an engine flush if you've got significant sludge buildup.

 

True. But he's in bad shape either way. I think that product is used by BMW owners to get rid of sludge. It was discussed here a few years ago.

 

@bmf4069 its between the dots, and consistently getting lower.

 

If it’s ring related, 1 quart trans fluid, rest oil, couple hundred miles, drain... sometimes it can free up rings

 

The OEM gasket is rubber. They get hard and practically become plastic. I really doubt you have a PCV valve issue.

 

Standard compression pressure for (Edit: 3.4L 5VZ-FE) is (Edit: 177 psi); minimum compression pressure is 148 psi.

https://www.engine-specs.net/toyota/5vz-fe.html

I regret to inform you that the previous owner sold the truck just in time...for him. I hope he priced it accordingly.

 

@empty_lord hey, for the trans fluid method, how long should I test oil when I add it to the mixture? Also, @JohnLakeman i got it for 1,800. It was a farm truck that only went probably 30 mph max for most of its life.

 

Hmm. If it’s lived a life of slow use, it may just need a good ol “Italian tune up”. Fresh oil and a good dose of driving it “harder” than normal may work wonders