Check Engine Help

teneightyloser · March 25, 2004

I just installed a K&N replacement filter in my 98 chevy, i drove it for the whole day, no problem, then when i got home, the check engine light came on, could it have anything to do with the filter? The EGR valve was causing the light to come on in the winter, but it has stopped since, untill now... What does an EGR valve do? and can i fix it myself, do you think that is the check engine problem, or my air filter. Also another thing, if i was to take the air box lid off to get more airflow, would it do bad for the filter or engine?

citydriver · March 25, 2004

The filter would'nt cause the CHECK ENGINE light to go on.You may have knocked something off/loose while changing it (vacuum hose or electrical connector)..look 4 1 of those 1st...when the light goes on it stores a trouble code,if you have an AUTO ZONE nearby they will read the code 4 you..EGR stands for Exhaust Gas Recirculation..it sends exhaust gasses into the intake to reburn them,also to help cool the valves and prevent pre-ignition...You should find out what the trouble code is B4 you throw any $$$$$ at the problem...If i remember correctly,the air box cover also holds the filter in place,so removing it could be a problem,but I'm not sure cause I have a '95 which has a different set-up

GMCTech · March 25, 2004

If this K&N is properly installed (oiled well) then it CAN set the check engine light.

Atomized oil can get through that filter. Usually only under high air demand conditions or if the filter is perforated, or misinstalled. But it is possible, and if the oil, or any contaminate really, gets on the MAF sensor it will cook it.

Also, if the filter is over oiled it can be an air flow inhibitor, and set a IAC code for inability to adjust to compensate.

If you don't oil the filter, it reduces it's effectiveness a bit, and won't ever be a problem.

Just remember after you clean the filter, allow it to dry completely. And if you oil it, inspect it carefully for tears of any size and be sure to install properly.

Hope this helps.