Technical Service Bulletins

GM Warns About Oily Air Filters

Order Reprints
GM Warns About Oily Air Filters

General Motors notes that the use of an aftermarket oil-bath air filter that is excessively over-oiled may result in any of the following:

  • The MIL may be on accompanied by a DTC.
  • The automatic transmission may shift early and/or late, slipping and/or damaged clutches or bands.
  • Engine drivability concerns such as but not limited to poor acceleration from a stop, stumble, rough idle and/or limited engine RPM range.

The oil used on the air filter elements may be transferred onto the mass air flow (MAF) or mass air flow/intake air temperature (MAF.IAT) sensor, resulting in contamination and poor performance.

The contamination will result in the grams per second (GPS) signal and/or the Hertz (Hz) frequency signal from the MAF or MAF/IAT sensor to be skewed, low or generally out of range. The Hertz and/or grams per second parameters on the scan tool should be compared to a like vehicle with an OEM air box and air filter under the same driving conditions to verify the cause of the concern.

Related Articles

Ford Warns of Weak Park Warning

Plugging an oily Benz

Oily Connector for Mazda

You must login or register in order to post a comment.