I recently bought a 2nd hand 2011 forester. During the first long drive i noticed it was consuming way too much fuel, 1 tank got below 300km, then i noticed the engine light and cruise control lights were on. I cleaned the MAF and everything seemed to be fixed however, the next day the same problems began again-lights came back on, poor fuel efficiency, plus, the car started stalling and the AC blew warm air. There was also a burning smell that smelt like a burnt fuse. If i take the MAF sensor out and the negative battery terminal the problem fixes itself, but the problems keeps returning after 20 or 30 minutes.
Besides these things, the car runs smoothly with no mechanical issues.
Does anyone have any advice?
MAF or oxygen senson problems
-
El_Freddo
- Master Member
- Posts: 12502
- Joined: Tue Oct 04, 2005 10:00 am
- Location: Bridgewater Vic
- Contact:
Re: MAF or oxygen senson problems
G’day Warumpi! Welcome to the forum 
Sounds to me that you might need a replacement AFM. I’m not overly familiar with the 2011 model, I thought Subaru did away with MAFs in favour of a MAP sensor. They could’ve gone back to a MAF…
It also makes sense that the O2 sensor could be dead, although I would’ve thought the limp mode would kick in quicker than 20-30mins of driving.
Have you read the codes? This will pinpoint what the ECU is complaining about. It also saves you chasing many “what it could be’s” until you hit the mark. Your wallet would probably be lighter by then too.
A mechanic should be able to scan your ECU for codes with the correct apparatus, some reckon you can do it on your phone with a dongle connected to the OBDII port. On the earlier models you could connect some plugs under the dashboard and count the long and short flashes to get the codes - then look up what these mean.
And keeping Steptoe’ pet hate in order - whenever talking fuel used and distance covered always use an amount of fuel - eg: 11L/100km or 55L to 400km - “a tank” can be any amount, or could be still quite full before refilling Old Steppy doesn’t get on here much anymore, if at all.
I hope this helps!
Cheers
Bennie
Sounds to me that you might need a replacement AFM. I’m not overly familiar with the 2011 model, I thought Subaru did away with MAFs in favour of a MAP sensor. They could’ve gone back to a MAF…
It also makes sense that the O2 sensor could be dead, although I would’ve thought the limp mode would kick in quicker than 20-30mins of driving.
Have you read the codes? This will pinpoint what the ECU is complaining about. It also saves you chasing many “what it could be’s” until you hit the mark. Your wallet would probably be lighter by then too.
A mechanic should be able to scan your ECU for codes with the correct apparatus, some reckon you can do it on your phone with a dongle connected to the OBDII port. On the earlier models you could connect some plugs under the dashboard and count the long and short flashes to get the codes - then look up what these mean.
And keeping Steptoe’ pet hate in order - whenever talking fuel used and distance covered always use an amount of fuel - eg: 11L/100km or 55L to 400km - “a tank” can be any amount, or could be still quite full before refilling
Old Steppy doesn’t get on here much anymore, if at all.I hope this helps!
Cheers
Bennie
