Hi Guys

I was driving for about an hour reached some traffic, and the had a sudden loss of power, the car was struggling when I put my foot on the accelerator in first gear, and eventually it turned off. Just been towed to the garage. When I arrived there started the car and the power was back and it was purring like normal!? Any ideas? Cars just had a service has been running fine, its a completely standard P1.

 

MAF sensor? Mine just went and appeared with similar symptoms although never actually switched off???

 

was the car struggling for power? like juddering? i took the maf sensor off a few mins after roadside and started the car and the problem was the same.

 

did the check engine light come on at any time?

Tony

 

Mine was juddering and the thing felt awful but i am sure that if you had taken the sensor off and it was still doing it then it can't be that. Sorry mate but you have reached the limit of my technical know-how!!

 

With a disconnected (but otherwise good) MAF sensor the car should die immidiately.
Engine running on with it disconnected is a sure sign of a bad MAF.

 

the maf was disconnected by me, i started the engine and it was still losing power like it wasnt revving properly and just feeling soo sluggish when i hit the accelerator. so I just turned it off. After an 1hr -30mins or so at the garage i started it and the car was fine. the power was there as soon as i started it, i had it running standstill for 5 mins. No problem.

It was a really hot day today, dont know if the heat caused it? it was just strange!

 

Maybe you did not understand what i said.
If the engine is running, and you unplug the MAF sensor it should stop running immidiately.
If it continues running the MAF sensor is near the end of its life.

 

It was still running, but seemed like it was on its last legs, no power, very sluggish and struggling even with it on. Basically the exact same problem. So you think its the MAF? because it was still running, but struggling like anything!

 

If it continues running , even very badly ,it leads me to suspect the MAF.
It should have died instantly when U pulled out the MAF sensor plug.

 

Why do you think after 90 mins it started normally and was running fine? No power loss at all, i left it running for 5 mins at least.

 

Lots of possibles...
Possibly dragged up some crap from the bottom of the tank,
dodgy o2 sensor,
MAF (i don't think unplugging it is really a solid confirmation of MAF failure, you need to see the running values to confirm a goosed MAF, im sure Mr Splitpin can confirm the best way to check for this)
Didn't the garage check the fault codes for you??

 

Bal it's probably something that was collected from the bottom of the tank..

 

@ Matt, I always thought that unplugging the MAF on a idling car should result in the immidiate cutting out of the car.

 

On some German cars yes, i think Subaru's aren't set up that way, not to mention a failed MAF may well be giving the correct reading at idle, but it could affect the way the ecu scales fuel as the rpms rise.