Zetec MAF sensor Dependance

Only today on a rolling road did a mate realise his MAF sensor was dead and the graph below shows the influence a dead one can have on the bhp/torque of a zetec engine.

In the black lines is the Torque and BHP with the dead MAF sensor connected.
In the Red Lines is the re-run with the dead MAF sensor disconnected.
(Note, even better power would have been achieved if a functioning MAF sensor had been connected for the re-run)



I noticed this as a member had this problem some months ago and the car was very sluggish at 4-6k and power would pick up again after 6k which is wrong for a 1.8 zetec. Once the MAF was unplugged, everything changed
So during a rolling road, another member came across this problem and its been identified quickly!
P.S - CO emmisions were less than 0.5% for the whole run... then after the maf was disconnected, we easily saw 4% CO emmisions.

This might be usefull for a sticky!
Dave