Have you read this bit Bill?
Ok the maf is likely to need a good clean ... but they're saying it wasn't permanently damanged ...
" 2. We coated both hot wire and film style sensors with K&N filter oil in both controlled (laboratory) and uncontrolled (real world) environments - none triggered check engine lights. We created extreme conditions, beyond anything an engine would ever experience such as submersing a MAF sensor in filter oil and monitored the sensor readings while spraying it with test dust. Even under these circumstances, the MAF sensor was not damaged. In addition, we were able to take this same MAF sensor, clean it, and found that the readings were identical to the ones taken prior to the extreme testing. "
They really seem to be taking the testing seriously .....
no i've not bothered reading K&N's stuff lately.
I haver seen over oiled piperX as an example kill a MAF dead. Was working fine the day before the owner sprayed his filter to oblivion... literally dripped.
Bosch MAF's on our cars are not very robust. The search function confirms this.
Vibration is biggest killer IMHO, followed by excess oil (be it engine breather fume oil, or getting excess filter coatings)
{edit}just had a quick read.
"Oil most often enters a MAF in the form of vapor via an engine’s PCV system. In an effort to lower emissions, positive crankcase ventilation systems use a PCV valve to draw fuel and oil vapors from the crankcase, this can allow blow-by gases to make it past the piston rings, and reintroduces them into the intake system upstream of air flow metering devices. When a throttle body or airflow meter needs cleaning, the oily film that is removed is largely a product of this system. "
Sounds familiar.. been saying the same for years. what took them so long