K & N Performance Filter

Price Paid:  $43.00 from Shucks

Year / Model Reviewed:
2005 Nissan Sentra 1.8S

Summary:
Used a K&N on my Nissan AND a 2006 Chrysler Town & Country and had better power and highway fuel economy. There was nothing earth shattering about the power improvements - just a bit more pickup - but the highway economy was a definite improvement. I saw a 2 MPG increase with the Chrysler and a 3.5 MPG increase with the Nissan (This is with a combined average mileage of almost 20,000 miles) but no noticible differences in stop-and-go MPG with either car. Mostly freeway driving and never off-road so I have not had a dust problem.

These work as advertised and seem to be adequate as far as filtration goes. Both the airboxes are sparkling clean.
I have never seen oil leaking or misting away from a K&N unless it was over oiled. REMEMBER - these are pre-oiled and do not need reoiling unless they are first cleaned using the prescribed cleaner. I suspect that most who had MAF damage have either oiled a non-cleaned filter or used too much oil when reoiling. These things come with an instruction sheet that should be followed. If you mess up your car because you can't follow instructions then it is your fault and not K&N's or the car mfg's.

The local Nissan dealer puts K&Ns into their performance vehicles - both the cold air kit and the air filters. Nissan sez to unhook the battery for at least 5 minutes so the computer will reset after you put the new filter in (or go back to the stock filter). Don't do it and the car won't run right.

With the Chrysler it was a simple drop-in. The service manager at the local dealership uses K&N and has for years. He sez he has never had a problem with one that was properly used. Of course, the local Mercury service manager sez not to use them so I don't in my Merc.

Strengths:
Work as advertised in most vehicles. Well made.

Weaknesses:
Expensive. Require some user maintenance, which may be beyond some users. Low restriction means less effective filtering than a paper filter so don't use them on your off-road vehicle of if you frequently drive on non-paved roads.

Similar Products Used:
Fram and Purolator stock filters

Overall Rating
 1 of 5

Value Rating
 1 of 5

Used product for
More than 1 year

Visitors rate this review
3.00 of 5, 2.00 votes

Price Paid:  $48.00 from autozone

Year / Model Reviewed:
2003 k &n filter

Summary:
I've used k&n air filters in 2 cars and 1 motorcycle over the last 7 years. There's one thing I can say from experience. They wear out the engine faster than a paper filter. Yes, they let in a little more air. They made the motorcycle slower and didn't improve either of the cars I put them in. Overall, I can't recommend them under any circumstances. Sorry, but that's been my experience.

Strengths:
Let more air, and more dirt, in than stock.

Weaknesses:
Throw off the air/fuel mixture balance. Wear out the engine faster than stock, paper filter.

Similar Products Used:
Stock, paper filters.

Price Paid:  $40.00 from autozone

Year / Model Reviewed:
1995 subaru/impreza

Summary:
I did not apply oil to my K N filter before I put it in my subaru. I have driven for about 10000 miles this way with now problems. I recently realized I had forgotten to oil it so I bought the kit and cleaned and oiled it. I read that too much oil has been (theoretically) causing problems with the MAF sensors of some vehicles. I was carefull in applying only the smallest amount I could, by my judgement. I installed the filter and after driving a few miles, my cars started hesitating and dying. My light came on so I read the code saying it was the MAF sensor. I can only relate the problem to the oil in the air filter because of the time correlation. Guess it could be a huge coincidence, but I doubt it. Goin to use MAF sensor cleaner and see if that fixes the problem.

Weaknesses:
Oil seems to mess with some MAF sensors

Overall Rating
 1 of 5

Value Rating
 1 of 5

Used product for
3 Months to 1 year

Visitors rate this review
4.50 of 5, 2.00 votes

Price Paid:  $9.00 from Advanced Auto Parts

Year / Model Reviewed:
2000 Pontiac GrandAm

Summary:
It was almost immediate, when I noticed that my car decreased in gas mileage (23 to 16 miles per gallon). About 6 months after installing the air filter, my car began to hesitate when shifting gears. I had 3 transmission specialists look at it and their response was that the transmission was going out. I had gone to Auto Zone about a year after installing the air filter and had a diagnostic test performed and it came back as a P0101. Come to find out, the oil from the K&N air filter had came off and covered my Mass Air Flow Sensor which had caused all the problems in which my car was experiencing. I find this out, however, after I paid to have a new Mass Air Flow Sensor installed and wiring. The technician explained to me that the signal circuit wire that runs from the computer to the MAF sensor was fluctuating and not keeping the 5 volts. This is what prompted them into replacing the MAF sensor and wiring. I paid over $300 bucks for this and come to find out, all I needed to do was clean off the MAF sensor because the oil had covered it up and was causing the computer to think that the car wasn't receiving the efficient amount of air flow. I purchased a Fram air filter and cleaned off the MAF sensor and now my car runs fine! I have nothing good to say about this K&N air filter and I wouldn't advice anybody else to waste their money!

Strengths:
NONE!

Weaknesses:
Causes oil to seep in and onto the MAF sensor and causes a decrease in gas mileage and shifting problems.

Similar Products Used:
Fram air filter

Overall Rating
 1 of 5

Value Rating
 1 of 5

Used product for
Less than 1 month

Visitors rate this review
5.00 of 5, 2.00 votes

Price Paid:  $46.00 from Auto Zone

Year / Model Reviewed:
2004 Mercury Grand Marquis

Summary:
Terrible product! My car ran bad for a week, and I had to take the filter out. Not only did the car feel like it was going to stall but the exhaust stunk like rotten eggs. The filter obviously let too much air in and ruined the air fuel mixture to the point where my car was running rich. I wish I never bought it. I hope my car is not damaged.

Strengths:
None

Weaknesses:
See above

Similar Products Used:
Paper Filter