M40 Engine - Air Flow Meter aka Air Mass Meter for e36

(can you see the flap inside the AMM?)



AMM or AFM controls the amount of air intake for combustion to take place in your engine, a flap controls this and when it gets jammed, engine will inevitably stall, this happens more frequently with an older car such as mine. As a result of this jam, the car will vibrate rigorously while idling, black smoke will emit from the exhaust. The overall performance suffers, i.e. pick up is slow or non-existent, auto-gear does not shift and all in all a higher petrol consumption, definitely not my idea of fun.


A brand new AMM cost around Sg$1,000 and there are no ready stocks available, a 2nd hand piece will cost easily $300 as well. But thank God for M&Q! They cleared up the jam by filing down the side walls of the AMM, the engine is much much more responsive now! See pictures to below...

(pix below is the AMM with the box covering the air filter removed)

(can you see the flap inside the AMM? see pix on the right hand side)

Below is the CO2 reader, a healthy reading is between 0.5 to 2%, mine was at 1%. After this tweaking, the ride is back in form, and for $50 it's very worth it!