I have a '01 Blazer/ Trailblazer that I installed a K&N about 30k/ 5 yrs ago and it seems like everytime I clean and reoil it I end up with an issue with my mass air flow sensor. I do not recall the codes that came up but I would end up having to clean the mass air flow sensor a few times within the first 1k of cleaning & reoiling it. It has been about 15k since last cleaning it and was wanting to clean it but I am just not in the mood to deal with issues like check engine lights and clearing codes.

So wondering if any of you guys are running a K&N drop in and do you have any issues when cleaning and reoiling?

 

Very simple, you're using too much oil on the filter. I wouldn't even bother with the K&N drop-in filter. Just use a good paper filter like Purolator.

 

Thanks for your input I think your right about too much oil. I'll try less oil. I'm going to stick with the K&N since it is paid for and actually works well after I get the oiling issue settled. I am surprised there isn't any other guys running a K&N's. I have K&N's on all my cars, truck and boat and the Blazer with the MAF sensor is the only one that gives me any trouble. So I'll try lightly oiling it next time and see if it is still an issue.

 

I agree, too much oil. The oil coats the sensing elements and heater in the MAF. This causes a drop in fuel mileage long before the check engine light comes on. Cheaper in the long run to put a Purolator filter in every six months.

 

Aside from using too much oil you are cleaning the filter way too often. You should only need to clean and re-oil every 50,000 miles.

And, yes, I've used K&N filters on all my vehicles for quite a few years so you are not alone.

 

Paper or dry flow filters > Wet gauze filters any day of the week... K&N's offer very little power increase / don't filter worth a damn and cause MAF issues like you're having.

Not worth it IMO. You'd be surprised at how much dirt a wet gauze filter lets into your engine...

 

Thanks to all for their input !!
You bring up the cleaning it only every 50k I have never gone 50k but I think you are on to something. I think your right I am cleaning it too often. Because I should have learned from the lessons I learned with my truck and the K&N. On my truck I clean about every 30-35k because it works best at about 10-30k between cleaning. Because for the first 10k after cleaning I get alittle turbo dusting. The K&N when clean it does let some dirt get by it isn't until it get about 5k-10k on it that it works best and still flows cfm's. I know some of you don't believe but there are flow tests out that prove a K&N flow more cfm than a paper filter even when paper is new and the K&N is dirty. But if you don't mind buying a new filter time and time again then that's cool. I would also like to touch on so called "Fresh Air Filters" if the dog gone thing is sucking air from the engine bay it isn't fresh air!! There are also other draw backs to them too but I don't even want to get into that. Sorry these are just a pet peeve of mine.

Now have you ever had any issues with your Blazer and K&N ? And thanks for pointing out something I should have known. So I think I'll let it be for at least another 15-20k and lightly oil next time. I'm bad I am heavy handed when it comes to oiling.

 

I've never had a problem with using K&N filters in my Blazer or any other vehicle I've had them in. That includes zero problems with the MAF sensor. Come to think of it, I do need to clean the one in my wife's Monte Carlo. Been awhile since I've cleaned that one.

As a side note (kinda), K&N actually recommends not cleaning the filter until 50K even if the filter looks dirty. Seems when they get a bit dirty they filter better than when freshly cleaned and oiled.

And you know? I've never found any dust anywhere inside the engine past the filter. Not sure where K&N got this bad publicity from. My cold air intake is as clean as the day I installed it with the K&N filter. Throttle body, MAF, etc all clean. The over oiling I understand but the rest is beyond me.

 

If you over oil it it will kill your MAF. Other than that it shouldn't be an issue. My blazer came with a K&N and my MAF was shot. I am sure they over oiled it.