Jonathan B

A lot of folks seem to have the same issues I've been struggling with lately - poor drivability, almost stumbling, as you get back on or off the gas, especially at low revs.

This gets compounded by soft engine mounts and the clutch chatter issue. (I'm going to put in the old filter again when I go to the dealer to get the clutch/flywheel fix done, just so they know how bad it really can be!)

I live in a dusty area, so I change the air filter every 6k or so - it improves the drivability for a while, but doesn't really solve the problem.

As I approached the 30k miles point, I put in a K&N air filter (just the drop in replacement for the OEM filter, not one of the cone shaped ones) - bingo! the drivability issues are solved, to the point that even the clutch chatter is mitigated. Great filter - I imagine that I will have to clean it quite a bit more often than the 50k miles recommended by K&N, though.

Cost? $33 plus $8 S&H from Jegs.com. I'm sure you can get it cheaper if you look hard enough! Since the OEM filter is about $15, and has to be replaced instead of cleaned, the K&N should pay for itself pretty quickly, too. Highly recommended, and about a 2 minute job to install.

JB

Roddimus Prime

Will someone please explain to me (ASE certified) how replacing your air filter eliminates clutch chatter?? This is the dumbest thing I've heard in a while. Also, K&N filters on MAF vehicles usually causes more problems than they fix. Too much oil coats the hotwire in the MAF and will cause sporradic readings.

leungwingkei

I don't see how a filter will eliminate clutch chatter too, as the filter affects the engine not the drivetrain.

Anyhow, the there's a TSB for the cold clutch chatter issue. You may be able to get the clutch replaced under warranty. Search the board for more info on it.

And replacing the filter at every 6K is a little too often, even in dusty conditions.

Jonathan B

I may not be ASE certified, but I can use a Thesaurus!

equivalents for mitigate:

alleviate
ease
allay
moderate
take the edge off
diminish
tone down

My point was that the 2 conditions can and do interact (ie, the poor driveability exacerbates the clutch chatter problem since it is impossible to open the throttle smoothly under conditions when the clutch chatter is likely to occur). Therefore, fixing the drivability problem makes the clutch chatter much less of a problem.

Did I say eliminate? Nope - the clutch chatter is still there, and is scheduled to be fixed at the dealer next week. It is just a little easier to manage, since it is much easier to add revs in small increments without the engine stumbling.

As for the 6,000 miles, that was based on my experience with my car in Southern and Northern California. I only replaced it if the filter was obviously collecting a large amount of filth (visual inspection) - and the alleviation of the poor driveability symptoms supports that it was in fact time to change the filter!

I've never heard anything about the K&N oil screwing up the MAF, but I'm already on my 3rd MAF anyway (1st 2 replaced under warranty in an attempt to solve the drivability issues).

Hope that clarrifies my first post!

JB

goldstar

Nevertheless, there have been numerous reports of oil from the K&N filter element being deposited on the hot wire element in the MAF sensor. When this happens, it prevents the MAF from taking accurate readings of the intake air density causing driveability problems. In order to mitigate this condition, it becomes necessary to clean the element with a solvent such as carb cleaner. You have to take great care here as it is extremely easy to permanently damage or destroy the MAF.

The deposition of oil is even more likely when a panel style K&N filter is used in the stock air box since the MAF is practically on top of the filter in this location.

maitai92

i added the K&N drop in filter to my P5 at 1000 miles. Didnt feel a thing. Gas mileage was the same. Maybe a better throttle response. (?). I then switch to AEM SRI and felt the difference. the car just revved freely all the way to redline. Real power wise maybe a few ( 1-2whp?) but Butt dyno definetly says 10 hp .
I think the main restrictions on the stock intake is all the whole intake track to the airbox. If you straighten the intake track to the
airbox its probably at least 3 feet long and another foot and half from the box to the throttle body.

UHZT

OK. I am going to talk about my experience.
When i replaced my OEM filter by a K&N drop in filter i definitely felt a better throtle response. We Know there is no HP gain.
Two days ago after 10.000KM (with the new filter) i check my MAF and i did not see any oil deposits, a litle bit of dust in the tungsnten filaments and in the temperature detector, that i cleaned easily.
I live in a dusty area 88 Degrees F (Caribean coast of Colombia).
It is possible after you have cleaned the filter you put more oil on it than necessary, it may be a cause of oil excursion.

Anyway you have to clean you throtle body, IAC control valve and MAF on a regular basis in dusty areas and follow strictly the instructions for K&N filters cleaning.

Regards
UHZT

Jonathan B

I've always had great experience with K&N's, my guess is it depends on the application whether it makes more power (I'm most familiar with MG Midget tuning - on these cars the right K&N filter actually matches the power of a no filter, ram horn setup (see the David Vizard book on tuning the A series for dyno runs to back this up).

For the Protege (a 2000 1.8L ES) I wasn't looking for more power, just tired of throwing away money every time I had to replace the stock filter, and getting improved drivability is a bonus.

One reason we may need to replace the filters so often is that last year, we lived in Orange County, and there was a large grass fire right behind our house (luckily, the wind was blowing the other way..... - this fire ended up causing a lot of concern in Rancho Santa Margerita and Coto de Caza), and up here we live very close to Dublin, where they use open fields as fire training for fire crews - hence lots of dust and ash in the air at certain times of the year.

I've had to replace the air filters in my wife's subaru more frequently than recommended as well - we know its time on her car because gas mileage suffers noticeably.

I've also had great experience with K&N's on an Alfa GTV6 (autocross car) and a Toyota MR2 (autocross/time trial/ daily driver) in addition to the Midget.

JB

Roddimus Prime

The only time I could see a noticeable gain with a K&N was on force fed applications. My 1976 Turbo Pinto used to just eat paper filters. I swapped out my papre filter for a cylindrical 3" K&N stack and had no more problems. Under boost you could litteraly watch the filter get eaten and sucked into the intake neck. Very scary!

pro-slug 2003

I think the only time you gain throttle response or power from a drop in filter is when your filter is dirty. When this occurs your air fuel mixture becomes more rich hurting power and causing flat spots. It is silly to think changing to k and n filter will give you more power especially in a new low mileage car.

distance

If you are stupid enough to over oil your filter then yes, the K&N is not for you. There have been people in the past to send K&N there MAF and found no problems with oil coating and the MAF had just gone south. The reason they sent it to K&N because STUPID dealer voided the waranty saying that the filter must have damaged the MAF. I have had My K&N in for a good 150 000kms on my merc mystique. I never over oiled it and when I did , I re-cleaned it and reapplied the oil AS DIRECTED BY K&N!!!!