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The Legendary Myth Of The Stuffed Afm, Please Put To Rest

rorz

By rorz,
in General Maintenance

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rorz Enthusiast

rorz

Posted
Posted

Hey guys, i've been searching the forums about air flow meters becuase i just put a Poddy on my RB30 and i've noticed a power loss in the high RPM and i am led to believe it must be my AFM,

So what actually makes an AFM stop working properly? Like people always say "oh yer mate yer AFM's had it eh"

But how does this happen? And why are they so prone to stuffing up whenever they like?

Someone please put the legendary myth of the stuffed AFM to rest!

Cheers

Rorz

cowie165 Veteran

cowie165

Posted
Posted

Missing at high RPM is likely to be a coil pack or possibly a dirty AFM.

If the AFM is cutting out it will run like crud for a second or two, then return to normal, rinse and repeat. This is usually due to dry solder joints and means the AFM needs to be repaired or replaced, not just blasted with brakekleen.

I think Steve writes about it in his thread that Craved linked to, but the dry solder joints cause the resisitance to go to infitinty with a consequent voltage drop to zero. Zero voltage means no input to the ECU so it stuffs around for a sec before switching to limp home mode, but by then the AFM usually kicks in again.

HTH

rorz Enthusiast

rorz

Posted
  • Author
Posted

ok cheers for the link i musn't have searched hard enough

Yeah sometimes when i go aroudn corners and straighten up it cuts out and jerks then comes back to normal again. So maybe my AFM is stuffed? OR maybe its just becuase its sitting a bit loose becuase of the pod filter moving around when i corner

cowie165 Veteran

cowie165

Posted
Posted

Yeah that's when mine used to stuff up. I found that I could cause my dodgy AFM to fault by pressing on the connector plug. It wont be doing the connection any favours, but if you idle drops and almost stalls then you've just found your culprit.

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