acko

hi all,
as the title says really.
Had my MY51wrx into the subaru garage at horncastle and they say the maf is on its way out, but my question is, " would this make my car run lean?"

thanks for your help

paul.

Slowboy Racing

Yes the maf sensor if used to determine the mass of air entering the engine. This information is then used to calculate the correct fuel mixtures, based on that if the sensor is faulty it will very easily run lean.

wrxmad

whats happening when ur driving??
i think i have the same prob?? but not sure.

Brun

If you have the smallest doubt about your maf sensor - replace without question

Brun

wrxmad - A failing maf sensor is very hard to spot as the ecu will adjust things to allow for it - but not enough. If you do an ecu reset, and your maf has been on it's way - the car will run very rich and very rough at tickover.
I replace mine every 18 months without fail as i have an MY99 which are known to have very weak mafs along with the MY00

funkyspider

I'm surprised that a subaru garage would let a car go out when they diagnosed the maf as failing. Buy a new maf and you only need the sensor, not the housing which subaru may try and sell you (about 80quid as opposed to 270 or so for the full housing and sensor). Yes it could cause it to run lean which could lead to det. Without being dramatic and crying 'melted piston' it will cause running problems of some kind

The ecu may not be able to compensate. If the maf is sending it a reading which is thinks is sensible, but doesn't reflect the actual volume of air then it can't compensate, unless other sensors are telling it there is a problem. If you've been told it's failing by a reliable source then change it - simple as

acko

the car runs very badly whenever under heavy load, for example, it feels like it wants to go but its forever holding back then all of a sudden it will go but very jerky. My boost gauge is flickering all over the place and the car will throw a CEL light but will go off again after 3 days.

Took the car to subaru and they tested it and it gave them a code but they couldnt say for sure which sensor it was for. They gave me 3 sensors that it might be and they were
1, mass air flow
2, lambda sensor(couldnt say which one)
3, fuel sensor ( cant remember the proper name)but that one was £400 to supply and fit.

Anyway the only way to find out was to have my car for the day and try out sensors of other cars and take it for a run on the road and they say its the mass air flow(maff)and are 100% sure of this, but for my car to give them a code and they wernt sure which one it was i think its pretty poor of subaru.

hope this helps in some way or you can even understand what im saying and thanks for the replys guys

acko

i asked the subaru garage about the damage this could do to the car with it running lean and they said because the CEL light was on and the code stored in the ECU, the ECU would not allow the car to run right and not let the driver go beyond the danger limits to do any harm

acko

ive got a new maff ordered from subaru and there fitting it on the 19th feb. I know it is dearer going down the subaru route but my car has been running crap for 3 mths now and i want this sorted right, so its going to cost me £320 for the work theyve already done, supply new MAF and fit it for me

Brun

Drive off boost till you get it fixed - that is a brave statment by the Subaru gararge

Brun

How much are they charging for the part?

acko

£180+vat for the MAF

Brun

Speak to the likes of Scoobyclinic to find out what they charge. I pay £85 ish for a maf for my MY99 and i can't imagine yours being that differant. To change the sensor is an under 5 minute job

acko

thanks for the info Brun but ive already got it on order from subaru, so a bit late now

funkyspider

confirm with subaru they have only ordered the sensor and not the sensor body which it sits in as I believe their standard policy is to sell you the whole lot, which isn't needed.

I'm shocked that they say that, maybe the newage ecu really is fail-safe ?
Unless anyone knows different.

Brun

Cancel it - If you've not paid for it they can't make you - simple

acko

i just want it doing now Brun because its been doing my head in for months now, so im going to stay with the subaru garage for now but maybe next time i will try the clinic, but just a bit far to travel because the wife has the car all day for work and 3 young kids doing cubs, swimming ect..... just awkward at times to get things sorted out

Brun

I'm not saying go to the Clinic - ring and ask for the price, you might save the best part of £100. Fitting does literally take under 5 mins

acko

sorry m8 i totally misunderstood what you were saying.

I think i will ring the clinic tomorrow to find out how much they are and see if they will deliver

thanks once again for your help

Brun