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What was previously thought to be a Coil Pack issue now looks like an Air Flow Meter problem.

My Power FC is showing an AFM1 reading of as low as 0.4 while AFM2 is steady at around 0.75. This causes the car to shake, idle rough and lose power while driving.

Sometimes this happens constantly. Other times the Power FC will show both AFM's hovering at 0.75 and the car purrs like a kitten and drives like normal.

Does anyone know whether AFM1 needs to be replaced or is this an issue with the connector/earthing?

I haven't tried cleaning the connector with a spray (I was planning on buying some spray tomorrow).

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"This causes the car to shake, idle rough and lose power while driving."

is the lose power while driving at any speeds, or while still in first? i know its a diff car but my BMW had a similar issue and it was resolved by replacing the MAF

Thanks guys!

The loss of power is constant. as soon as AFM1 voltage drops down, the car starts shuttering like it's choking. Every gear and no particular RPM. Had to roll home slowly.

I unplugged AFM1 and it started shaking etc. Plugged it back in and it started idling perfect. This is why I'm thinking maybe its the wiring and not the actual AFM.

As mentioned by basti sounds like it could be the solder inside one of the units meant to be a common thing that can happen ! Are they standard AFM ? Swap them out with someone see if that fixes it if so might be time for an upgrade! Nismos maybe ?

Or just leave them plugged in and run a map ecu. Standard sir

lol he's on his P's in a car that is FAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAR from stock.... AFM's are the least of his worries :P

Chris just swap AFM1 with AFM2

If AFM2 starts playing up you know it's the AFM. If it's still AFM1 then it's electrical.

Realistically though they usually don't drop to 0.4 - they will drop to 0.0-0.03 which will make them flash error/failure intermittently on the PFC... That's just what I found over the years anyway.


Ditch the AFMs, hide the plugs, and get a PFC D'jetro :D

And go through a roadside EPA station and fail instantly because they can't find the plug or do find the plugs, pull them off, car still idles ok - instant fail and easiest way for them to check for full aftermarket setups. Once they get you that way you just get written up for a full inspection on the spot and then they get the camera out which is the worst thing that can happen :thumbsup:

lol he's on his P's in a car that is FAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAR from stock.... AFM's are the least of his worries :P

I'm off my P's now :)

Chris just swap AFM1 with AFM2

If AFM2 starts playing up you know it's the AFM. If it's still AFM1 then it's electrical.

Realistically though they usually don't drop to 0.4 - they will drop to 0.0-0.03 which will make them flash error/failure intermittently on the PFC... That's just what I found over the years anyway.

Good idea Ash. I'll swap them around and see what happens.

AFM2 is a pain in the ass to get to lol.

If I need to replace the AFM, I doubt I'll be able to get one in time for Tony's wedding!

AFM2 is a pain in the ass to get to lol.

Because GTR.

I remember Ash popping a cooler pipe at DECA in someone elses GTR... Full toolkit, 2 guys who know their way around.... 30+ Minutes later...

UPDATE: I swapped the AFM's around and it's still AFM1 which has the voltage issue. I guess this rules out an issue with the AFM.

Anyone experienced this before? Could it be the wires leading into the connector?

Because GTR.

I remember Ash popping a cooler pipe at DECA in someone elses GTR... Full toolkit, 2 guys who know their way around.... 30+ Minutes later...

That was a pain in the ass, inner guards & supports FT, we cut corner and didn't put anything back in though L lol

AFM's are a bit more fiddly, not too hard though - certainly need less tools :D

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