Engine oil in spark plug pockets

[NoDak Ninja]

Hi all,

My wife got in her Bravada this am and got an oil dangerously low warning. I pulled off the resonator (that's what you call the plastic part on top that the intake air flows through, right?) and there was some oil in the resonator and a lot of oil under the resonator. It was puddled on top of the engine. After wiping up the oil, I then pulled out the coil packs. The front two were basically full of oil, and the oil level got lower as I went back, with none in the back one.

This is my wife's ride, and I don't give it the attention I should. Apparently this has been going on for a while and I didn't catch it. It does use oil (I think I know where it's going!) Any ideas how to remedy this?

 

[mrrsm]

The COP (Coil On Plug) Gaskets surrounding your Spark Plug Wells have long since flattened out and dried up and get brittle and break down. You can see how dramatic this can get from the attached comparison views of New v.s Old; noting how "round" they start out as... and how "flat" 240,000 Miles of use can make them wind up:

View attachment 79980 View attachment 79981 View attachment 79982

The result is that they leak Motor Oil being sprayed around under pressure beneath your Valve Cover, filling up the Spark Plug Wells. And if present in the resonator after 14 years... the same Motor Oil has been ingested as Oily Vapor; deposited inside the Resonator Chamber and has likely contaminated the MAP Sensor at the back of the upper Intake Manifold as well. Be careful not to damage this sensor by cleaning it with too much heavy solvent spray. You can use Hot Water and Dish Detergent in the Sink to scrub out the insides of the Resonator after sopping up all of the Blow-By-Oil and then wipe it dry.

As long as your Spouse did not run the vehicle very long after the crisis presented itself... No Harm Done...and as long as you don't remove or loosen any of the Spark Plugs before cleaning out each of the wells with some absorbent towels... and a light spay of Brake Cleaner and blowing them clean (watch your eyes here) with either some cans of Computer "Canned Air" or using compressed air... and again.. No Harm Done. The COPs will need to be cleaned of all Motor Oil before being plugged back on top of the Spark Plugs.

Since her vehicle is likely fairly High Mileage by now... more frequent Oil Changes and "Level Checks" are in order as all older vehicles consume-burn oil in quantity as they age out. Be advised to ask her whether or not she has been adding any Motor Oil... as an Over-Filled Crankcase makes more Oil available to be Whipped around and wind up in the Resonator as the Positive Crank-Case Ventilating action draws contaminated air through that small, bent up Rubber Hose underneath the Resonator into and through the Throttle Body...and the heavy oil separates out ...and settles therein.... or further down inside of the Intake Manifold as well.

This is the least expensive set of Silicone Gaskets that you need to purchase and while cleaning everything correctly and seating each of them with patience is required or they will leak all over again from coming out of their respective [ ] Square Grooves... spending a little quality time when tidying up the Valve Cover now... will mean years of trouble-free service later on. Don't skip replacing the Outer Fastener Grommets... Those Old Ones need to go, too:

https://www.amazon.com/DNJ-Engine-Components-VC3190G-Gaskets/dp/B00TM28OVE/ref=au_as_r?_encoding=UTF8&Make=Oldsmobile|51&Model=Bravada|568&Year=2002|2002&ie=UTF8&n=15684181&s=automotive&vehicleId=1&vehicleType=automotive
View attachment 79979

 

[Sparky]

Or, something else that simply may need done is just snug down the cover bolts to seal up the gaskets again. Very well may not need all that disassembly and work. Try the simple (and free!) thing first BEFORE tearing a bunch of stuff apart. Note that I've successfully stopped (or 90%+ stopped) oil leaks on a few different vehicles simply by snugging down bolts. And if you get it 90% stopped, well, then it is up to you whether the extra work is worth that last 10% (it wasn't on my 02, you're almost always going to have a little seepage into those plug wells at some point anyway).

By the way, an 02 does not have a MAF, and even if it was newer than that and had a MAF, that sensor is right after the air box. You'll never get oil from the intake resonator all the way down that tube to get on the MAF.

On the oil in the intake resonator and such, my coworker's 07 Trailblazer was getting all gummy from oil coming through the S shaped PCV hose to the resonator. It didn't seal right. She replaced it and, while I'm not entirely sure why, her oil usage dropped a fair bit after that and far less in her intake. She has over 250k on her truck, by the way.

 

[Mooseman]

Another thing you can try before replacing the valve cover gaskets is to snug up all the bolts, as suggested by @Sparky and to add a washer (or two in your case as it has a fairly significant leak) under the coil bolt heads. Pull each bolt out of the coil by turning it counter-clockwise, add appropriately sized washers and put them back on the coils. This will add a little bit more pressure by the coil onto the valve cover to compress the hardened and shrunken plug well gaskets.

While you're there, after cleaning out that oil, might as well replace the spark plugs (ACDelco 41-103 ONLY).

BTW, '02 was the only year that had that low oil warning system. It wasn't so low that it ran dry so it's all good.

 

[NoDak Ninja]

I thank all three of you for the great advice. I will try snugging down all the bolts and adding some washers to the coils. My first thought was valve cover gasket. If the bolt snugging doesn't work, then I guess that's the next step.

One thing I am happy about is the low oil warning system that Mooseman mentioned. While trying to figure out what the heck was happening, I fired it up for a few seconds. It sounded fine actually; no knocking and the pressure gauge showed just under 40 PSI. Not ideal obviously, but not blown up either.

Thanks for the help. If something new pops up tomorrow, I'll be back! ;-)

 

[Mooseman]

The oil pressure gauge is fake so don't bother even looking at it. It's basically an idiot light system with an on/off pressure switch. Only if you have no pressure it goes to 0 and gives a warning. Otherwise, the PCM fabricates the readings on the gauge for entertainment.