I've had an intermittent problem - or possibly two problems - for some time now. It/they are very intermittent and so difficult to pin down. I thought I'd throw it out to the brain trust here. These two issues may or may not be related (I suspect they are) and they don't happen simultaneously.

#1 - Intermittent MAF 01 errors. The MIL will come on, I'll download the MAF01 error code, car doesn't seem to drive any differently, then anytime in the next 10 minutes to 3 days the light will go out again.

#2 - Engine lugging. With very light throttle, e.g. driving in a garage, coming off idle into traffic the engine will lug. ie I won't get much power but it will sort of surge in pulses. I cannot reproduce at will. It seems like it is happening most when the manifold pressure is lowest; coming out of overrun with light throttle, or coming off idle with light throttle. To me, it feels like a very small intake leak - unmetered air getting in somewhere.

Anyone seen these issues?

 

Have you tried replacing (or cleaning) the MAF sensors? Check the connections for frayed or broken wires/insulation? Bad MAF reading can cause the lugging.

 

They have been inspected and cleaned, but not replaced. I'm not one to just swap expensive components "just in case" it fixes the problem.

To me, the two problems together indicate a tiny unmetered air leak somewhere. Not that familiar with supercharged engines, more of a turbo guy, but I'm sure same principles apply.

 

The most replaced intake part is the "T" at the front, where both air inlet tubes meet and join onto the throttle body. It's a somewhat fragile piece. Worn engine mounts can play havoc on that part since the engine will move but the inlet tubes won't. Lots of heat in that area also.

 

Ugh that reminds me… need to make an appt to replace my mounts. Engine and trans.