Valve Cover Gasket Leak?

Correction: Lexus and Cadillacs is the only thing I have seen them on.

 

Look bucko.

I've been twisting wrenches since 1967.
I'm only 50.

I'm GLAD that carbs are a thing of the past, and I'm glad that my crankcase ventilation system doesn't cover my engine with an oily mist.

I run from ASE because they have done stupid things such as:

'91 Ford Escort trans blew up. Got it back, car was getting 20mpg (was getting 35 before) and was not shifting right. "Tech" told me that I was lucky, his Ranger only got 18. Service manager told me to pound sand because the OBDS didn't report any problems. Trans blew up AGAIN, fixed again, tech wrote on the paperwork that it appeared that I had done a neutral-drop. I refused to sign the paperwork. Funny funny... car was back to 35mpg.

Left the radiator cap for my '94 Toyota pickup on the distributor after changing the exhaust manifold. I found it after seeing steam after crossing a 5000ft pass.

After performing a brake recall on my wife's '00 Echo, doing SOMETHING wrong that resulted in the inner brake pad separating from the caliper.

Having my wife's '04 Rav4 for 3 weeks trying to troubleshoot a CEL. Finally swapping ECUs. When we got it back, missing items included the lower engine cover, 3 ground wires, and the battery compartment cover retaining clips.

Her Rav, my '03 Tundra and '06 Silverado have not been back to an "ASE" service point since and wowee... haven't had a lick of trouble with any of them doing the work myself including the timing belt on the Tundra's 4.7

 

You actually admit to working for Claremont Toyota?

 

I'm not sure working for that particular dealership could pay for gas to get there.

The dealership is, or at one point was, owned by Cal Worthington (it was when I went there).

And no, I never worked there.

 

Define reputable please. Lots of shops claim to be, but most are not.

Draft tubes didn't have a Pollution Control Valve. Just a breather filter in the valve cover and a down draft tube coming out of the crankcase that pulled a suction when going down the road.

 

LOL!

Seriously though... the fact that I didn't know you were ASE speaks volumes.

I have too many certifications and qualifications to list on a resume. If someone asks, they get the short list that pertains to their project and needs. An engineer that needs someone who specializes in spread spectrum ethernet communications couldn't care less if I'm trained in bench repair of HV power supplies.
But I don't throw up my certs in someone's face as a counter to an argument. All a cert means is that someone was able to stay awake and remember enough to pass the final test.

Actions speak louder than words... or certificates.
Every time a "tech" is challenged, the next thing he says is "I'm ASE/MMI/AA/BS/PhD"
Sure they are.
And how do you refer to the guy who graduated last from medical school?
"Doctor"
That simply means "I don't have a logical answer"

 

Yup. The modern PCV and EFI systems are part of the reason that we no longer have to change our oil every 3000 miles, or change our plugs every 12,000.

 

Bingo.

Couldn't have said it better.

 

you sir, are correct. "ASE" is a joke. Does this mean ALL "ASE" techs are idiots? No, it does not. Does that mean "other" None "ASE" "techs" are immune to the same laziness? No.

But i have similar experience... and I'm no where near as old.

Moral of the story? Turn your own g-damned wrench and do it right the first time. even if you have to do it 3 times, it'll cost you less then paying another monkey to do it wrong the first time.

 

well, i seem to not have those issues....



and i could still argue messing up your ubolts and having your torque wrench laugh at you is still going to cost you less. plus think of the price you cant put on knowledge.

 

A very effective method of learning is by trial and error.

A less painful method is learning from the mistakes of others

 

those are some awesome shop rate hours in your area!

 

Pretty sure he's talking about paying for access to download that portion of the Toyota manual.

 

whoops that was my bad. took that as paying 15$ for someone to do the work!

 

Shit, I'll work for an hour for a pint of Guinness!

 

I had gasket covers replaced earlier today. Took a few hours I took a few pics while the mechanic. Was working

 

I too have “seepage” towards the front of the valve cover on the passenger side of my 2008, 136k mile v6. No issues, just adding that I have this too. I’d like to spray & wipe it off with some brake cleaner but I’ll probably do that with the engine off because someone said something about vacuums. Oh and I did just change my PCV valve when I did my spark plugs a few hundred miles ago. Maybe I should clean it off and see if changing the PCV valve has any effect on the speed/rate at which my seepage seems to be occurring. Maybe what I just said actually makes no sense, not sure.

 

Newby here, if vc leaks then excess air could be drawn in. Would this not set up lean condition p0171 cel?

 

No.

It doesn't work that way. Due to piston blow by there is a slight pressure in the valve cover area.

There is a suction on the valve cover via the PCV to the intake that mitigates excessive pressure buildup in the valve area and crankcase.

https://www.youtube.com/watch?v=DTlCep4_jZA

 

I see it a lot on BMW and Volvo. Euro manufacturers are fond of building air/oil separators into the pcv systems. It allows the oil to "fall" back down into the pan and only the crankcase gases get routed back through the intake manifold. Over time these (plastic) parts get soaked with oil and become brittle.

On BMW lots of cracked pcv lines down at the base of the dipstick tube. Volvos often have a plastic oil filter housing/separator bolted to the block that likes to split open.

This results in unmetered air and will eventually code

The best way to look for intake leaks on these types of engines is to smoke them right through the dipstick tube. You can also test the health of the pcv/separator system by putting a vacuum gauge on the dipstick tube. It should read a very small amount of vacuum, like 1/2 an inch for example. Positive pressure is not a good sign. A small amount of blowby is normal but too much and the pcv system can't keep up. Thats when oil starts getting forced past crank seals and other gaskets.

Toyotas have well designed pcv systems though, less plastic to break.

All cars are different, with different crankcase ventilation designs. Sometimes it depends on small differences in how the efi system keeps an eye on itself mixture wise. Some are more tolerant than others about detecting unmetered air.

For example, Subarus have 2 rubber pcv lines that go from each valve cover up to the intake ducting (held on with cheapie clamps) right before the throttle body. Ive seen them come in with the hoses hanging off and no codes

Long story short, on our trucks, any crankcase leak can result in unmetered air but it would have to be a pretty big hole. Like the oil cap gets left off or a plastic pcv hose breaks in half. Oil would be spitting everywhere, you'd be able to smell it