Talked to the dealer today to get a K&N filter and he told me that Polaris has issued a bulletin that a K&N filter will DAMAGE a EFI motor... Has anyone heard this???
It does damage automotive cars, why would it bother a 4 wheeler. I know that it may lean it out BUT mine hasn't run this good from the factory since I installed the filter, and I haven't enrichened the fuel at all.

 

Do a plug check, and make sure you are not running lean. I just think running a drop in K&N going to make it run that lean.

 

I don;t think a K&N would really cause a problem either. I had a friend on his car that through a check engine light and the car would not run becuase he did not wait the proper dry time after serviceing his filter and oil covered the MAF sensor and IAT sensor.

I don;t know much about polaris's EFI system but they may not have programmed backup tables into the computer to compensate for a sensor failure. this is just a guess though.

 

Believe it or not he told me it would harm the "Sensors". All they have is a "Air temp",
"MAP" and a "Throttle position"sensor....your guess is as good as mine.
He swears it came from Polaris!

 

Check the plug to be sure you don't have a lean condition.

As far as oil on sensors, yes it happens, and yes it can cause problems. The sensor will not function properly and could indirectly cause a lean condition as a result of a providing a false reading to the computer.

The only way you will get a benefit of a k&n on an EFI quad that doesn't have a MAF sensor is if you are running rich. Then the K&n will add more air to the mixture, hence more power.

If you are NOT running rich with the stock filter, then adding a K&N to a non mafs efi quad won't do a thing.

Does this make sense?

 

It is the oil getting on the mass air flow sensor that will damage it. Make sure you don't over spray your filter. Almost all car manufacturers ask when you bring your car in for service if any aftermarket parts are installed especially if you bring your car in for a "check engine" light. I keep the original air filter for all my vehicles and just replace it if I have to bring in my vehicle for service. K&N says it won't void the warranty, I just don't deal with it.

 

The EFI bikes do not have a Mass air flow sensor.

 

Exactly, so there won't be an adjustment for the added air flow of a K&N.

 

Guys you do realize that K&N filters don't filter as well as the stock paper elements that you have right? The reason that they flow better is they have larger voids in their medium that allows for more air flow. Because the voids or holes are bigger larger particles of dust and dirt can bypass the filter and be ingested in your engine. Seems to me it's pretty dumb to run a less effecient filter on a machine that runs in EXTREMELY dusty conditions.

Personally I challenge anybody to dyno run a quad with a k&n and a paper filter and show that you got improved performance.

BUTT dyno results don't count in this challenge.

James.

 

Well if it was me, I'd just ask the dealer to see the TSB and see what Polaris has to say about this issue.