Is there a better/more accurate way to test apart from the stall test? Should the engine be hot or cold or doesn't it make a difference?
On my MY99 with Tek3 i still get hesitation and on a recent rolling road was only showing 215bhp instead of 260-280 i was expecting although the torque was over 250 lbs. I disconnected the maf (renewed within the last 12 months)
and it nearly stalls but doesn't.Is that a pass or a fail? Does it stall straight away if the maf's dodgy?

PeteS

 

Erm - It should stall with MAF disconnected!

 

Thanks Tony

 

Had similar concerns regarding MAF sensor - I did the disconnect and it stalled straight away. It did not even seem to attempt to run.

 

BTW - it is not a failsafe method of finding a failing MAF - Just an additional check that can be done!

I think the only true way(s) of testing are to read the voltage the MAF is sensing (not sure on what it should be) or replace the MAF and see if the problem is cured!

 

I think you're dead right there Tony. I had a MAF problem where it hadn't failed totally but it wasn't outputting the full voltage range.

The ECU was coping with it, but after an ECU reset as part of a tuning run the problem came to light as all of a sudden the mapper could hear detonation events. Quick MAF swap and the det was gone.

 

On another thread i see that you should have a reading of 1000-1300mv at warm idle.How do you take this reading?Is it via deltadash or similar?Or can you just stick a multimeter on it?How do you get a reading at idle?(no air flow?)

PeteS

 

Anyone?

 

Can be tested with a multimeter on the wires (would have to check which pins to use) - their will be airflow at idle, as if the car is ticking over at 750rpms, it must be getting air to keep running.

Easiest way is with deltadash though!

 

Or with a SECS....3g/s at idle....right on the money!

 

hi i put a k&n air filter on my98 uk turbo. now when the car is warm and i stop at traffic lights e.t.c. it drops revs but doesnt stall. i've heard that after market air filters can kill mafs is this true or do i have some other problem. thanks

 

After market air filters can kill the maf by 2 ways....

1-Excess oil in filter that fly to the sensor.
2-Excess vibration, because the short tam (etc) is not firmly secured!

Other that that, maf failes happen to stock ones also....

 

Oh...and do an ECU reset if you change the air filter....

 

thanks think i'll try putting the standard box filter back on and see if it makes any difference