I found motor oil in my stock intake box a few days ago, my filter (drop in K&N) was covered in oil so was the bottom of the air box. I cleaned it and also clean the filter. and today there was oil again, no as much but enough to dirty the air box again, but this time i took it to the dealer, and 4 tech and a few service advisor told me 2 different stories. so said that this was normal with new engines, cus its old oil from my oil engine that as in the pvc line. but that does not sound right. and the others said that they never seen this before. They said that it might be oil that when down the wrong line when the oil was done. cus there is i hoes that it connected to the intake. the only thing that they did was give it a good cleaning, and to keep a eye on it, if it happens again then they are going to install a warranty location kit so that the oil travels in a different route. I know this sound messed up and weird, but has anyone else heard of this before?

 

search catch can
did you fill oil recently?

 

I'm guessing you have a 2004 or '05?

Prior to '06, the crankcase breather hose from right below the oil filler neck routed directly to the intake just ahead of the accordion hose (and the MassAirFlow sensor).

Overfilling oil caused your problem.

BUT in normal use, oily gunk accumulates in the intake, and can cause the MAF to mis-read. It also gets on the throttle plate, and the other air control valves in the intake.

For this reason, in '06 Mazda re-designed the PCV system.

There is a Technical Service Bulletin: http://www.finishlineperformance.com...50-06-1664.pdf which describes this and shows the new 'kit'. (this is the "milky dipstick" TSB)

If you are out of warranty, instead of doing this TSB kit at the dealer, others have simply installed a catch can to trap residue and oily vapors. Search user "Kane" for a simple and elegant solution.

 

^ your post pwns mine

 

^yeah, but it took longer to type so... you win!

 

perfectly normal!!

 

normal in the sense that it was designed this way to help lubricate the throttle body plate and valves downstream.. but an excess amount of oil will be detrimental..

 

No, it was designed for emissions.

Just disconnect the hose on the oil spout. Put a filter on it and cap off the other end.
You will never have a problem again.

 

This topic seems familiar . . .

 

no whay!! This happens our cars?

 

fixed yet?

 

either fixed or the car blew up by now

 

This would be funny if you read the post....Stock intake box with a drop in filter....but what do I know.

 

that looks like my pic in the old days. lol

after that time, I keep my oil level right and never happen again ... oh did I said da oil level right ?

 

till yesterday there was no oil in the intake box, now it starting again. i was driving the car at 170km/h and the CEL started to flash, and the car started to slowed down, so i turned it off and started again this time getting to 193 km/h and no CEL this time, so i check the intake box, and there was the oil again. so back the the dealer.

 

quite the speedster huh

 

Could be a clogged cat converter or bad engine. Happened to me with both of these.

 

al,

I understand the blowby from the bad engine pressurizing the oil up the filler, but this is the first I have heard of a bad cat forcing backpressure.

Any idea what seal(s) blew? Was the engine F/I?

 

you know, Ive never had this issue in all my years of ownership and mines an 04. Huh, maybe I should just do an oil catch can to be safe

 

Both of those situations have caused oil to be forced up into my intake. I don't have an explanation, just experience.