kn filter too restrictive? wtf?

I was at the dealership getting my 4.0 tacoma looked at for my horrible gas milage yesterday. The tech took one look at my drop in KN filter and said that was my problem and to throw it away. He said that when they get any dirt in them at all, they are too restrictive. He said to go back to a stock paper filter and that will fix my problem? I have yet to buy one, as he knows more that I, but has any ones else heard this? I don't want to say he is full of it, but that does not make sense to me.
They also recommended that I try cleaning my MAFS, can you do this, or is is it sealed? They wanted 170.00 do clean it. My check engine light is not on, but they said it has some tolorence before it will come on.

 

You can clean the MAF. I've never done it on a tacoma but many in the forum have and I'm sure they will post soon on how to do this. Also, I can almost guarantee that you could buy a new MAF for 170 so don't let them do it.

 

Your MAF is probably clean as a whistle. My 4.0 has 32k miles and the MAF is still clean. But if you want to clean it just take it out and gently spray it with some air intake cleaner, then let it dry. The MAF sensor is on the intake tube before the throttle body. I think 4 screws hold it in.

 

He's just another K&N hater....

You should keep your K&N clean and clean it regularly. I used to clean mine every 6 months regardless.

Sure - the K&N can get dirty and probably more restrictive than when its cleaned. But I can't imagine it's any more restrictive than a dirty paper filter!

 

Here's an interesting video about different types of filters:
http://www.youtube.com/watch?v=ThmW2SW1I-k

 

So any one tried pone of these true flows? I could not find just a drop in filter on their web site for the 2nd gens.

 

I just bought a True Flow Intake System, They were on sale.... I should get it within 2-5 days....

 

I just bought a True Flow XDI and should be here today

 

So it couldn't be that the trained tech has a lot of experience, both with K&N's and in general, and he's simply giving this guy the benefit of said experience? Maybe he's done oil studies, like I have, that show higher amounts of silicates when using a K&N vs an OEM filter (all conditions otherwise equal).

I personally wouldn't use the K&N. I did for years but after what I saw in my oil studies and the couple of failed MAFS I've had (different vehicles), that's just my personal choice.

 

There's tons of arguements FOR and AGAINEST K&N filters. If K&N filters are as bad as a lot of folks think they are - the company wouldn't be in business. But obviously, they continue to make them and sell them.

I highly doubt a Toyota Technician is an expert on K&N filters. Anyone can perform studies and anyone can read about studies performed about them - that doesn't make you an expert. The only people qualified to be experts about them - are the engineers who've designed them and tested them (and continue to test them). *On a side note - some Toyota Techs can't even do their own job let alone be an expert at anything*

In this situation - The Toyota Tech is being lazy. Immediately blaming the problem on the K&N and rendering his job *done* without checking into other things. Not to mention - in the process, pissing off the customer (JDB).

Like everything else in the world - (as you mentioned above), it's a personal choice. I've had K&N for years on various vehicles and I've never had any problems or complaints about them. I'd buy them again. So who's right?
Nobody is right or wrong. It's personal preference.

 

Well my 0.02 cents....I have run K&N air filters for many years of drag racing and on the street..had my car dynoed many times...and the K&N cone type always flow the best. Never had problems with dirt getting into motor and I take off the intake a few times a year and its spotless inside. K&N also dynos their applications so you know how much HP yor going to get and they can't lie about it becasue every performance mag out there has tried them and reported the numbers on various applications.

I have never had a problem with the mass air; maybe if someone over oiled the filter and did not let it dry they may have an issue.

As for true flow; while I have never used one...my thoughts:
- I watched the video and they used a K&N without oil which nobody would ever use? Why? I find this kind of a dishonest comparison.

- Also my main issue with the design is the filter has two purposes...filter the air...most will do this great even the cheap paper. But function two is to allow as much air into the engine as possible....I assume this is why 99% of everyone that buys these filters/intake tubes wants one for the possible promise of a little more HP. Well True Flow has no numbers on their applications and admit that the K&N material flows better.

Personally I like K&N and have put 100s of thousands of miles on them with many applications and only ever had good results. Just clean it when you change you oil; oil it and let it dry.

 

Sorry for going off topic.

05PreRunner, thanks for the video. I watched the whole thing. I am going to check out the website and get more information.

It would be great to hear what type of results people have been getting with true flow on a 4.0 tacoma.

 

+1 It was some good info there. I can't say one way or another if the K&N was oiled or not, but it was interesting to see how much dirt gets through. With all the dirt roads and road salt in my area it got me thinking about getting one! And that doesn't even count the off roading I do on dusty trails. Just normal, everyday driving.