problems with air mass

[merc_tech]

hi. im having problems with my air mass on my mk6 1.6 zetec. whenever it is plugged in, i dont seem to have any power, but if i run the vehicle with it unplugged, i have power, but its overfuelling, which is a bit of a pain as now the m.o.t is almost due.
any ideas???
please help

[Dave_ST220]

Well if you've been running for any time with it off you may have killed the CAT thanks to the over fueling. Have you got an induction filter? Have you cleaned the MAF with IPA solvent?

[merc_tech]

ive got another cat to stick on it. i took another air mass from another escort 1.6 zetec, although that one would run fone, when on my escort, doesnt seem to work. i am running with a k&n, although it started doing this before i stuck it on. it seems to do it mainly when it is up on engine temp, so im wondering if its actually an o2 problem???

[Dave_ST220]

Heat soak? Open filters will always loose power is roasting hot engine bay. Check the plugs for tracking as well.

[merc_tech]

hi, its not a heat soak problem. the filter has a constant cold air feed. its really strange. i replaced the plugs and leads today, and now it seems to run fine with the air mass unplugged, although if i plug it back in, the same problem occures-no power. do you think it could be a wiring problem or a fault stored in the ecu???

[neiljohnson]

Air mass sensors do go wrong on the Ford engines but try cleaning it out with some solvent cleaner first as when you run upgraded air filters the oil from the cotton gauze gets onto the sensor causing incorrect readings. The reason it goes better without it plugged in is because the ecu is switching to a base map as it has no readings from the sensor which is why it is over fueling.

[focusboy]

trying to clean a maf sensor is a total myth, the only reason people thinks it works is because the ecu knows when it has been disconnected, and when its disconnected it remaps to run on a higher petrol burning ratio, have you tried having tour car read by a diagnostic tester yet? if you have tried another maf sensor and you still got the same problem i personally would start to look at the egr system and make sure thats working properly

[Dave_ST220]

focusboy said:

trying to clean a maf sensor is a total myth, the only reason people thinks it works is because the ecu knows when it has been disconnected, and when its disconnected it remaps to run on a higher petrol burning ratio, have you tried having tour car read by a diagnostic tester yet? if you have tried another maf sensor and you still got the same problem i personally would start to look at the egr system and make sure thats working properly

Not true i'm afraid.