MAFT Gen 2 - Anyone?

[TurboBob]

There could be a couple things happening.

The PCV system changes flow depending on vacuum, so there could be issues with air bypassing the MAF by going thru the PCV system. This would reduce the airflow signal and might put the ECU into decel enleanment.

Your bypass valve might be leaking, causing turbulence at that throttle opening.

At certain throttle openings, the airflow thru the MAF is most likely not uniform, as the throttle blade is mostly closed, and is 'sipping' air around the edges. This will cause the MAF to read lean.

Blow thru systems tend to take more tuning as the turbulence can be unpredictable.

Once you can log, we can tune this out.

[twinturbvr4]

Sounds good Bob,

when you say bypass, do you mean the BOV? if thats what you are referring to, without having any leak tests to back this up, I'm pretty certain it is not leaking, the pull-type has very good open and close action and closes up very quickly after releasing.. and opens even under the slightest boost after the throttle is cut.

Would krankvents help in the pcv system? I've also been fighting what I believe is excess crankcase pressure as I had to double up my oil cap gasket and still have some trace amounts of oil coming through the breather at the end of the pcv system.

I will hopefully be getting a scanmaster in the next few weeks.. for now I am trying to adjust the MAF gms/sec settings to accomodate and try to richen it up for when I get back on the gas after a shift.

thanks!

[twinturbvr4]

bumper..