i’ve been having some car trouble over the past couple of days ('02 Neon, stumbles, bucks and kicks at wide open throttle, check engine light flashes, runs fine otherwise) and i’ve been running possibilities by the gearheads in another forum, one of them has the opinion that the standard K&N air filter is essentially worthless and actually performs worse than the stock paper element, and the oil ends up gumming up the airflow sensor(s)
so, what’s the Straight Dope on K&N air filters…
FWIW, K&N and others say the problem is caused by too much oil in the filter.
it’s a stock K&N preoiled from the factory, haven’t cleaned it yet…
I have a K&N in my wife’s car, and I have one of their FIPK II preformance intakes in my truck. I haven’t had any problems at all, and my truck’s performance (noticably the throttle response) has increased. My wife has an 02 dodge caravan with the 2.4l 4 banger. I’m guessing your motor is either the pretty close or the same. when you put the filter in did you do anything else? pcv valve, plugs & wires, oil change? i’d first go back and check all the vaccuum lines, sensors, and especially Mass air flow sensor. IIRC trying to run her engine without the air intake connected caused the engine to run rough while i was trying to clean the throttle body, very similar to what you’re describing.
They do exactly what they’re intended to do. Whether or not they do a “better” job than the stock filter is debatable. I’ve used them for years on cars and motorcycles both with and without MAP/airflow sensors. Yes, they flow more air than the stock filter, but that may not mean anything, and it might even be a bad thing.
If you’re retaining the stock airbox, it’s likely that there’s some restriction there, by design. Modern engines are designed so that the intake, fuel, and exhaust all work together, and diddling with one usually requires diddling with the others. This is further confounded by computerized systems, and can go as far as upgrading/reprogramming the computer or using an aftermarket “performance” MAP sensor. It gets real complicated real fast.
Bottom line…K&N is a fine product, but it’s probably not going to solve your problem. I’d stick with the stock paper element and get the car running right. Don’t cloud the issue by adding another variable.
Unfortunately, you’re probably going to have to have a competent mechanic connect the car to a diagnostics analyzer. Chances are the stored error codes in the cars computer will point you in the right direction
I had another thought last night after I logged off. Did you unplug your battery before installing the filter? A sudden change in the amount of air flowing into the engine without resetting the computer could make the engine run rough.
it was fouled plugs and arcing plug wires, new set of plugs and wires and it’s good as new
Ahh, all this WAG-ing going on and it was as simple as bad wires, and fouled plugs. Well, at least it wasn’t anything expensive.
I’m going to add one note to this thread. I wouldn’t put one of these on a diesel engine. At the Ford dealer I work at I’ve seen a couple of engines that ingested dirt and were ruined by it. Both had K&N filters. To be fair, the owners never seemed to service them, but they also seem to filter out less dirt, and they go downhill fast if you don’t service them regularly.
Congrats, my friend. It pays to check the simplest (and cheapest) stuff first, before jumping into more complex issues. Eliminate the basics, then start looking for more convoluted possibilities…
I run K&N’s on my two YFZ 450 quads in the Sand Dunes of the Calif Desert.
K&N’s filtering materal is oiled cotton.
I’ve been duneing for several decades and know a lot of duners.
www.americansandassociation.org I post under yfz450kid.
Never has anyone that I’ve talked to had any engine problems that they attributed to failure of their K&N airfilter.
They do need to be cleaned with a mild, preferably K & N cleaner, washed then dried, then oiled.
Re-oiling between cleanings is a smart move too.
An outerwear cover over the filter helps as well.
Having said all the above, and the hyppocrite that I am do I trust mine?
Nah, not really.
Foam filters seem to be more fail safe and forgiving if one neglects them.
K&N’s not. Ya gotta be on the ball if ya use one.
Not for lazy people.