Hey there

I have a 99UK Turbo wagon. Its completly standard. I noticed last night when driving it that at around 3k theres a slight flat spot developed. Its almost like the cars is coming on and off boost and when you accelerate past 3k the car slightly holds back and hesitates. Its not a violent hestitation, but its definetly noticeable. The car seems extra thirsty too at the moment so i wonder if the 2 are connected. No other probelms. No ECU light or anything. If it is MAF how much is a new one?

Cheers everyone

Andy

 

Does sound like it could be the MAF. What's it like at idle?

Costs about £70>£80 to get a replacement.

Cheers,

Rich

 

It hunts slightly at idle, but nothing dramatic.

Andy

 

Defo sounds like your MAF is on it's way out. my99 prone to the problem.

Your lucky really cause it cost me £280 to get mine fixed. I had to buy the sensor and the housing. On the my99 model you can just buy the sensor.

If you know of anybody with the same year car try and swap it out to see if it still happens. If it does then its not the MAF. If it doesn't then you need a new one.

Seems to be a lot of MAF's failing at the moment.

Cheers,

Rich

 

22794AA010 Meter CP-Airflow about £75

 

Andy,

Yep, sounds like the MAF to me. You just need the sensor (about £80) a specialist can change it with their eyes closed too! It's very imp that you drive the car gently off boost until you get it sorted. MAF problems can cause fueling issues that can lead to det if you start giving it some beans!

Take it steady mate.

NS04

 

Thanks everyone. I'll get myself a new MAF then. Anyone got a link to a pic of where it is? Ive worked on a lot of cars so i'll do it myself. Ive never had to touch the scooby though as its never gone wrong before ;o)

Cheers

Andy

 

Next to the airbox is a large dia pipe leading to the engine.
The MAF is housed within this pipe.
Unclip the grey wire connector the undo the two holding screws(you need a Security Torx bit).

TBH, Once you have the new MAF it becomes obvious where the old one is & how its fitted.

Chris

 

Ok then, cheers for that.

I'll let you know if it cures it.

Andy

 

I have a similar problem - It has gone in to get the MAF replaced under warranty - Will let you know if it dissapears.

 

If its not the MAF then it could be the Lambda - that would also explain the thirst

Chris

 

Hi,

I had the same problem on my MY99. Replaced the MAF and had the boost solenoid cleaned - now runing like a new car!

It had been really hesitant through the rev range, especially pullling form around 65-70mph in 4ht and 5th. Since replacing maf and cleaning b/s it just pulls and pulls!

All the best

Dave.

 

Is the Boost Solenoid cleaned with carb Cleaner? and where is it on the car?

MAF .... well, I am a sceptic on this - the MAF is blamed for all sorts, from flat tyres to faulty headlamps!

However, please let us know if the MAF helps!

Surely the new MAFs dont have any problems? Subaru must have sorted any issue with it by now!

Pete

 

Don't hear too many issues with MAF sensors on the newer cars.
But they are a weak point on the classic shape. At least with the my99 model you just need to replace the sensor and not the whole unit.

Would be interested to hear if any issues with the MAF on newer models though.

Cheers,

Rich

 

Pete,
The MAF is sensative on the 99/00's, and although blamed for all sorts, it is more than likely the cause of the original posters problem.
Boost solenoid can be found on the drivers side suspension turret - cylindrical thing with two pipes and a couple of electrical wires coming out of it. One pipe has a 90 degree kink in it 1" from where it connects to the solenoid.
Clean it by disconnecting the pipes, put the ECU into test mode, and spray in brake cleaner- it should click a few times a second if its clean & working.

Chris

 

Cheers Chris

What is meant by the MAF being 'sensitive'???

I assume its a hot wire system? Therefore is it sensitive to current flow? Air flow? What?

Or, is it sensitively built? Therefore Subaru would have toughened it up by now?

Pete

 

The early MAF's were a hot wire but the 99/00's are a film type (thin metal strip).
Oil vapour, fine dust etc (anything that passes through the air filter) can clog the surface over time, resulting in a misreading MAF.
Not 100 % sure what type they changed to for the Bug / Blob's, but I believe has now been sorted.

Chris

 

Heres an update guys....

I wondered if in fact it was a fuel problem. The last time i filled up i used texaco super instead of optimax because i was too lazy to drive accross town and get some. I let the tank go to reserve and tanked up on optimax and so far problem solved.........the car does surge very slightly hovering around 3k but nowhere near as bad as before.

 

I would still check the MAF out as if there is a problem with it you could make it worse by not doing anything.
Just get a diagnostics report and see if it flags up anything i.e. error codes. Should cost a bout £25 for a garage to do it.

Prevention is better than cure

Cheers,

Rich