I have an 04 supercrew FX4 with 24,000 miles on it. As i drive on the highway and floor it the truck starts to sputter kind of a hesitation, i can hear it in my exhaust. i also hear a noise from the engine area like a misfire. anyways i take it to the dealer and they tell me that the K&N air filter has made the truck run lean and has ruined the plugs. I only have the drop in filter and i really dont think that is the cause. I have had the truck since it was new and the filter has been in it since day 1. the truck runs fine until i really get on it. what do you guys think, is the stealership full of it? they want to charge me $205 to change the sparkplugs, also if the problem isnt fixed they say they will reinburse me but what if it is something worse are they also going to blame it on the filter. i know its a long one

 

sorry, i cant think of the name, but i believe there is a law that states that a dealership/company can not void your warentee due to a reusable air filter unless they are willing to replace them at thier own cost for the life of the autombile. its something to look into. i think the k&n i bought came with a copy. let us know how it turns out. it seems like most of us have a drop in or cold air intake.

 

Whatever program mechanics go through to earn their wrenching abilities absolutely programs in their heads that aftermarket filters are the end-all of engines. I have in person seen mechanics (mostly old ones) get ALL worked up and go on and on about how terrible K&N filters are and that they let dirt in the engine and the oil ruins them blah blah.

Well, there is *some* truth in that. For one, OVER oiling a filter can and WILL lead to problems in the engine. However, if used properly it is certainly a better filtration system than a stock paper unit.

If you have cleaned and re-oiled your filter, you may very well be at fault. Sorry

My buddy did that on his Tacoma and ruined some sensors and he was out $500 from his trustworthy honest mechanic.

As for the plug job, tell the dealer to shove it. Go buy plusg elsewhere and install them yourself or with a friend's help.

 

Sounds like an assload of BS to me. There is a spark plug tsb covering spark knock. Try telling them that.

 

Lumadar i havent gotten to cleaning or oiling the filter yet. i havent touched it

 

here is some reading for you....
http://www.knfilters.com/warrantyletter.htm

 

If the mass air sensor was contaminated by dirt/oil from the filter, yes, it's possible.

 

GM actually has a Technical Service Bulletin out about the oil from reusable air filters contaminating the sensor wire in the MAF sensor. That could give you a drivability problem as the sensor would give a false reading but I have never seen an air filter ruin a sensor. If the sensor wire gets coated (or you suspect it) just clean it off. I have used carb clean with no problems but now they have a new cleaner made just for MAF sensors. I say clean the MAF sensor (even if it doesn't look dirty), change the plugs (yourself or with help from a friend), and tell the dealer where to go.

 

On cleaning the fine wires and other sensor exposed areas, use no residue electronic cleaner.
Safer and better than carb cleaner. Some carb cleaners can eat plastic. Some will not, but how sure are you what's in that can?

I got a can of brake cleaner from AutoZone the other day, it was full of engine degreaser...
And even with the correct fluid, some carb cleaners are pretty wicked stuff.

Electronic contact cleaner is available from Radio Shack or many other places and leaves no residue, is safe for all electronics and most plastic and rubber products.

Frankly, I don't believe the K&N actually caused a problem, I think it's just another dealer with an attitude. Local dealer won't do anything on warranty unless you have all service done there, including oil changes, and considers your warranty void if you use aftermarket parts. They tell people that they know about the Magnuson-Moss Warranty Act, but dare you to sue them.

Not a problem, most people take their warranty work to the next closest dealer, 50 more miles but well worth it.
Chris

 

I know for a fact that if a dealer has over a certain amount of warranty work done, Ford will make it difficult for that dealer to cover certain warranty items. I found this out when trying to get my taillights replaced (leaking so bad it took the chrome backing off). I always took it to the dealership i bought the truck from, great guys, especially the service guy i always delt with. (they: rebuilt the rear end, new front rotors, new throttle body, replaced outside temp. sensor). When i took it in for the lights, he told me he would have to take a pic of the tail lights and send it to Ford to get approval, he suggested i go to another dealership. I asked whats the deal? and thats when he told me about the problem with the amount of warranty work and how Ford deals with it. So I took it to another dealer, no questions asked, they replaced them. I say try another dealer.

 

How many miles do you have on the truck? Is it still under warrenty?With the spark plug issue on these motors I would let the dealer change them

 

Good Point. I should have specified. I have used Castle Dragon Fire carb cleaner with no problems.

 

I say BS....a plain k&N filter isn't voiding a warranty...I'd print out the link from the k&n website and take it in.

There is no way they would get that money from me without a fight.

 

I agree 110%!

 

Was there a 'check engine light' associated with your problem, if so what were the codes. If it was a lean condition was it one cyl, one bank or both banks. The code or codes pulled by the tech would determine this. If it was both banks lean it would likley be a problem with the intake on up, such as a vacum leak, failed TB gasket or loose air intake tube. It is unlikley that both HO2 or O2 sensors failed at the same time. If the lean condition is isolated to one cyl or bank tell your dealer he is full of crap, because a "faulty air cleaner" would affect the entire engine. Also any additional air flow gained by your air cleaner will be measured by your your MAF sensor, and the fuel trim is adjusted accordingly. The extra air gained from a typical after-market air cleaner will NOT exceed preset factory measurments.