Ford Focus (1998 - 2004) - 03 1.8 MAF readings?

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Mon 6 Oct 2008 19:38
03 1.8 MAF readings? - djmontara
hey,
was wondering whether anybody knew the correct readings for the maf sensor on a 1.8 petrol zetec-e engine at idle and at wot (in lbs/min). need to check whether mine is functioning correctly as im having acceleration problems even though ive changed the whole ignition system and fuel delivery is fine and theres no vacuum leaks..

the car is an '03 with 42000 miles on the clock..

did a few tests on it, basically with the maf connected, the exhaust tone is sputtery at idle and when u blip the throttle WOT, it pings.. engine doesnt sound smooth either, coupled with the poor acceleration... (i couldnt even overtake a car..) but when i disconnected the maf, the exhaust tone became smooth, and when i blip the throttle wot, it doesnt ping anymore.. does that indicate that the maf is faulty?? would be really helpful if somebody could give me some values so i can compare them with the readings im getting..

just to give more info.. at idle, my stft and ltft are both around -2.3... but when the engine is under load and i do WOT, my stft shoots up to +19 for a bit and then corrects itself.. i heard this is characteristic of a dirty/naff maf.. but i just want to make sure before i fork out the money to change it..

thanks for all your help guys!


matt

Edited by Pugugly on 06/10/2008 at 21:02

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Mon 6 Oct 2008 19:48
03 1.8 maf readings? - Screwloose

I've never seen any car's data in lbs/min - kg/Hr maybe. MAFs rarely fail on these and your LTFT [additive or multiplicative?] is fine. [STFT is instant, so will change under acceleration.]

Check that your breather hose hasn't split - that's the usual.
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