K&n cai caused oil leak?

[Claybraham]

im new to the forum and I'm sure this has been asked before. Please take it easy on me lol. I have a 1990 GMC Sierra, 5.7 tbi, five speed. This truck didn't leak any oil until I put this cai on it. Seems to me like it's leaking oil on the back side of the intake. I installed it exactly like the k&n directions said. Could this happen if the engine isn't breathing right? Pcv is good. Only thing that's not hooked up that was before is a hose on the passenger side that went to the stock intake. I'm sure it's apart of the emissions. I drove it around and when I parked it I noticed the leak. It's a lot! It's coming from the passenger side, right down the side of the transmission. Thought maybe a valve cover gasket but I checked it and it was fine. I thought maybe the oil pressure switch so I checked it and it seems fine. Before I installed the intake I replaced the clutch, new rear main seal, and new oil pan gasket. It's clearly not the rear main cause I see oil coming down from top of the transmission. Any help with this or suggestions are much appreciated!!! Sorry for the long post. My only idea is that it's not breathing right

 

[df2x4]

First of all, if I were you I'd take the K&N off and put your factory intake back on. The factory setup flows more than enough, and already draws cold air from the hole in the fender. The K&N is a big crappy open box that draws hot air straight out of the engine compartment. Also the oiled gauze K&N filters are garbage. They don't filter very well, and they're prone to bleeding oil into the intake tubing and fouling up your MAF sensor. The only CAI for these trucks that's equivalent to the factory setup is Volant, and I seriously doubt even their product offers any gains over stock. This is coming from someone running a K&N on one of my trucks. The only reason I haven't put my factory intake back on the red truck is because I can't find the box I put it in. I had multiple issues with the K&N filter oil fouling my MAF, and subsequently replaced the filter with an Amsoil Ea series conical filter. Fixed that problem, but it's still a crappy hot air intake.

Second, I don't think there's any possible way that the installation of the K&N could cause an engine oil leak. Something else weird going on there.

 

[Breakdown]

You might gave popped the intake manifold gasket. That and the oil pressure sensor are the only things I know in that area. Trucks just marking its territory haha.

 

[Claybraham]

lol that's what I've been told. Idk I was also told that with too much air or the motor not breathing right could cause the sudden leak. One way to test I guess would be to put the factory setup back on. Thanks for the help guys! Maybe someone with a K&n cai could post a picture to compare, I'm positive I have it installed correctly.

 

[df2x4]

I'd post mine, but it's on a V6 Vortec truck so it probably wouldn't do you any good.

I'd try and figure out what that small hose you're talking about is for, and why you weren't able to hook it back up after installing the K&N.

 

[GL1500]

Your engine is an air pump. Air is drawn in through the intake and pushed the exhaust. Unless I'm missing something your new air intake doesn't create additional pressure such as a supercharger would so there's nothing to create an oil leak.

The passenger side hose that you weren't able to reinstall, where does the other end attach?

Are you sure your pcv is good?

 

[Claybraham]

I'm trying to upload a picture now. If it uploads, I wasn't sure what to do so I plugged it with a filter

You must be registered for see images attach

 

[Claybraham]

It's the little grey filter. I'm sure the pcv is good but I bought a new one just because. I haven't had a chance to mess with it though

 

[Claybraham]

The kit did come with a filter that goes on the drivers side valve cover. Instructions didn't say anything about it. Maybe I'll put that on when I get home and see. Maybe it really doesn't have anything with the cai at all. I just find it weird

 

[df2x4]

Like I said earlier, I'm pretty positive there's no way they could be related.