MAF Help

[AlexHillTVR]

Hi guys,

Just fitting my new MAF which is the 5AM unit, different to the previously fitted one (original early 1993 spec) in that it actually has the wire mesh at the front. Only thing is my air intake pipe doesn't fit over the bottom end and simply wont fit no matter what I do.

So I've gone and stuck it in a reverse layout, with the wire mesh now at the plenum elbow and the plug connector closer to the wing, rather than the engine. It seems to fit this way but will it work?

Basically how does the 5AM AFM/MAF generate its output signal?

Any help would be amazing.

[AlexHillTVR]

I'm using the ACT intake hose kit by the way.

[phazed]

Alex.

if your unit is wrong then i have an original 5AM unit spare and am in Surrey.

[taylormj4]

I believe the 5AM measures air flow using a heated wire. The air flow cools the wire thereby changing its resistance. The higher the flow, the cooler the wire. In that regard it wouldn't seem to be important which way the air flowed. However, I believe there are drillings that allow airflow other than through the main body and not sure if those matter.

[yknot]

'The wire gauze is needed to reduce turbulence around the airflow sensor', so I don't think it's possible to reverse fit your AFM without affecting the output signal to the ECU.

[blitzracing]

The mesh side has to be on the air intake side to get the correct reading- you can remove the lower casting off the first AFM and swap them if the pipes wont fit- just be careful with the gasket as you take them apart, or make a new one out of cardboard- There are various castings out there depending on the original fitments- but assuming its a Lucas 5AM- not a 3AM.