BMW E30 Pierburg and Weber carburettor (M10)
What usually fails on a Pierburg 2BE carburettor?
The most likely fault is the carburettor's electronics. Using Pierburg's repair instructions, the carburettor has been made to work like new. New spare parts are not available, so old parts have to be sourced from other carburettors.
The carburettor's second throttle does not move with the throttle cable - is that a fault?
No. The second throttle is not operated by a cable; vacuum moves it, controlled by the engine control unit. The throttle staying still when you press the accelerator pedal is therefore normal.
Why does a Weber replacement carburettor use a lot of fuel?
One cause is the rubber flange between the carburettor and the intake manifold. If it is damaged, extra air gets into the engine and consumption rises noticeably. The BMW part number of the flange is 13111278994.
Can a Pierburg carburettor be swapped for a Weber?
A Weber does not fit the M10 intake manifold directly; an adapter plate is needed in between. It is best to buy the plate together with the carburettor.