hi i was wondering if u can help me my 51 1.3 ford fiesta flight started to over rev when started and continue at a constant speed when my foot was off the accelatrator. We got a diagnostic and found the error code p1504. So we checked the air filter and was fine aswell as renewing the idle air control valve. But the car is still idleing very high. Can u help me.

p1504 is iac circuit which is most likely going to be you iac (idle air control valve) they get dirty and stop working you can try cleaning it but its prob worth just replacing.

yeh have replaced it but still reving high got any other things u think i should do

could be the MAF sensor? have you also checked and changed the Air filter as necessary?

I don't know whether this helps but we had a 2000 Ka with the same engine which required some "reworking" of wiring to the throttle position sensor and was a known fault at the time. Do the revs drop when the car is stationary? Ours only used to rev high when on the move, like when changing gear, but would drop to a proper idle when you came to a complete halt.

have checked air filter and is fine and about to buy a new one and it revs high for a while when sationary and sometimes drops down to normal idle. Thanks for help guys.

ps where would u find the maf sensor