So i've got an odd one here, after coming to a stop with the clutch down and still in gear my NA S4 start to idle very rich 10-11afr on my gauge but as soon as I pull it out of gear it returns to a steady 13afr idle.

Any ideas?

 

I think that should be pretty normal? Fuel map is designed that way possibly.

 

Thats would you would think yeah, but it richens up to 12.0 on my afr gauge just sitting in 1st gear with the clutch down not moving until I pop it into neutral.

 

I think Mazda use a sort of anti stall feature, when they are not in neutral, the ECM changes things, I wonder if the timing advances, and the AFR changes?

My 93 B2200, when it had the stock 2.2L EFI engine, would bump the RPM by 100-200RPM when I put it in gear, with the clutch pedal down, as soon as its back in neutral, back to idle RPM. The RX-7 would have the same sort of programming I bet.

 

theres no switches in the transmission except the 5th gear switch which makes the computer lean the mixture while cruising

least thats all that I know of