K&N Air Filter... don't buy one

[98conti]

Long interesting story. I just bought a 1998 Continental with the DOHC 4.6L modular engine. My problem started when I replaced the standard paper air filter with a reusable K&N air filter. The oil in the new air filter coated my MAF (Mass Airflow) sensor after about a week. The car started shifting erratically and bucking and jerking. I took it to a local Ford dealer and had the transmission flushed. During the service some transmission fluid sprayed on the engine so the tech had the engine cleaned. The car then became almost undriveable. I found some articles on the Internet about the K&N filter coating the MAF and that it can be cleaned. I cleaned the MAF sensor with electronic spray cleaner and cold drivability became perfect. When the engine heated up it started missing and still had erratic shifting. I found a FORD TSB regarding water in the spark plug well, 'Engine - Rough Idle/Engine Miss/MIL ON/Codes Stored Article No. 98-6-2'. Water had gotten into the spark plug wells during the steam cleaning of the engine creating a short from the COP (coil on Plug) to ground due to excesive moisture. The fix was to remove the moisture and apply RTV sealent to the area at the wire harness grommet where it enters the spark plug cover. I was able to determine which COP devices were having problems using a Autoxray EZ-Scanner 4000. It told me which cylinders were mis-firing.
So.. 1- Use a stock Motorcraft air filter and 2- don't steam clean your engine without applying the RTV sealant to the spark plug wiring harness.

[Towncar]

Excellent writeup !!

I've had the same problem with water in the plug wells. I have heard from diehard K&N folks that lighter coatings on the air filters cure the MAF fouling problems.

I'm with you though, no K&N experiments for me !!

[boxcartommie22]

i been using k&n filters for along time.. i never re-oil my filters i just buy a new one..i clean the maf sensors routinely along with the throttle body..they are very clean!!! no residue..i use these filters on my other 98 fords also..when i swiched to a paper filter the check engine lite went on..i had to dixconnect the batt. and then it went off..with the paper filter from baldwin i notice a diff. loss of power...changed the filter back to the k&n and reset the comp. and the power is back...people should clean their maf a couple times a year with elect. cleaner even when using paper filters and some paper filters have some oil in them too.

[boxcartommie22]

when i wash my engines i use the car wash blowers to blow the wells out besides my plugs are covered with bolted down covers..i then spray the entire engine with a mixture of vinylx and water which coats and seals, and protect the wiring and platics rubber etc.i also coat the wires with a antioxident compound from idea called noalox.you can get this at home depot for about 5 bucks