Marlon

Has this been a 'documented' issue on the 993 or Rennlist Forum? If not, how come?

JasonAndreas

My first post warning about this (that I could find) goes back to 2004. I help a few other 964 and 993 owners with servicing their cars and noticed the same problem on the other 964s but it wasn't until last October that I had enough independent evidence to start a thread with photos (linked to in my previous post). The problem with the 964 cover is that you don't really notice the problem unless you're looking at it from the rear of the engine, and most people don't drop their own engines. The 993 cover is basically (for the most part) the same piece as the 964 cover so the situation is the same. If the 993 part has the same problems (which appears to be the case from Eric's 993) hopefully we'll have some more photos to document the problem and warn people. The one "complication" is that Eric's airfilter is one of the newer types that doesn't have the polyurethane frame, instead its made of paper and that probably contributed quite a bit to the filter collapsing on itself? The urethane filter will just warp and not filter properly.

Marlon

Un believable! Maybe simply removing material (covered in previous post) from the center section of a spare stock air box cover would be the most prudent approach for this type of mod.

AOW162435

Correct. And costs substantially less than $175.

Andreas

JasonAndreas

Absolutely! The dremeled cover will still fit properly and the stiffening ribs will prevent it from warping.

C4S_fan

Glad that you figured it out and that it wasn't something more major.

I'd recommend AGAINST the K&N filter as several people have had issues with the oil used to lubricate the filter can cause the filament/sensor on the MAF to fail, and thus cause the engine to hunt.

Greg H.

I thought the issue with K&N air filters is that they pass more dirt unless over-oiled.

Greg H.

Steve Weiner-Rennsport Systems

Yessir, and thats precisely why we have always modified the OEM part,...

MrRoboto

Actually, the exact same thing happened to my stock cover. Why? Because one of the tabs were broken.

Toga

I'm not using my K&N filter since a few years. Because of what you say, but also because of something I read in another thread a while ago: if you over oil it, you risk to have oil coating around the air sensor inside the air intake. Causing problems to your engine management control.
I met a guy this week at my BMW dealer. He was having trouble with his engine while using a K&N filter. The "stealer" change the "flowmeter" and charged him $$$! I explained him what my thoughts were, being not sure that we can clean the sensor if it's oiled.

Jeff96-993

Two bad experiences with the Fabspeed cover here. Both were gifts from other people who noticed the problem, figured I'd take it off their hands and be more successful getting them to work right. Never did.

I fitted, refitted, and refitted again to make sure the cover and filter were properly aligned. No luck, the filter always collapsed inward.

So I did as Steve W suggested, I took a stock lid and carved away most of it.

Biggest benefit to cutting your own is that you can leave enough to better protect the filter from water spray.

Bull

+1 with many cars also.