Ok, had a maf problem fault code 23, so bought it of a winker on here and changed it.... Was ok first day , but left it for a couple of days and now code 23 pops out again. Is there any chance something elese is not wright causing maf faulty??????

 

Things to check: Wiring problem, or an air leak downstream of the MAF sensor (split hose, leaky dump valve, perished vacuum hoses etc).

 

What type and model year is your car?

Also, can you re-interpret "bought it of a winker on here" into something that we can understand? Are you saying you bought a secondhand sensor off a w*nker on here, or did you buy a brand new one?

Finally, can you confirm for us whether you reset the ECU after fitting the "new" sensor?

As Ali says, about the only causes for the code 23 error are either a wiring short or break between the sensor and the ECU, or a failed sensor.

 

^^^ Sorry my bad,,,as i'm at work and had to type it quickly.. Yes the maf is second hand but it's in good working order as the seller told.The car is sti v3 and the maf is from sti v3 type r, the battery was disconected while i was changing the maf which took me about 30 mins or so. Maybe i should kept it disconected a bit more??? The car was running ok most of the time with the old maf as well, it's just sometimes the ride was realy ruff and the car was jumping (sorry for my english) So i've been told by a guy who works for Zen to change the maf. Did that...first day it was ok, but after few days the problem came back....

 

It might be fine, but the problem with secondhand sensors is that you can never be certain.

Disconnecting the battery is a bit haphazard. The best way to reset the ECU is the proper way - this is the "connect black and green plugs, start car, drive slowly and wait for the Check Engine light to flash a uniform on-off-on-off" sequence.

If there's still a problem with the airflow sensor (or its loom) after you run this process, it will give you the error again rather than flash the all clear, at which point you know you either have a problem with the sensor, or with the loom. The sensor itself is much more likely a culprit.

 

It's becoming a pain in the a*£$% >>> After reseting the ecu the fault code 23 has gone, but!!!! Yesterday had a little journey, after stoping at traffic lights the revs started jumping making the car stall...It started ok so i drove to the petrol station , connected the wires to check the fault codes...It's all clear!!! started again and continued the journey...no probs...
Today in the morning , started the car to warm the engine up and after 3 mins it started doing the same thing...revs up&down...making the car almost stalling. Opened the bonet and when the car is reving up and down u can hear the air filter constantly soaking air in very loudly...Any sugestions????

 

If you've now got no fault codes present on the ecu, and the idle is fluctuating up and down, it may be worth giving the idle control valve a clean with brake cleaner.

Then reset your ecu (as suggested above) and take it from there.

 

Tnx Rich i'll try doing that... Also the revs are not flactuating at all times....to tell u the trueth i'd like u to inspect the car in general and we could speak bout what needs to be done regarding the map etc., Pm me when u have free time please, and i'll give u a buzz.

 

I have a very similar fault, but its got to the point where the car wont even start now... the air filter was very noisy when it was running though, hence why i imagine its a similar fault to yours. Did you get it successfully diagnosed and fixed in the end? Wasnt a MAF/Lambda sensor was it by any chance?

Cheers.