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3.9 V8i engine idle speed

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Range Rover Blues:
It's the lesser of evels I'm afraid, when cold there are lots os things getting damaged, including your pistons not being the right shape!  The engine needs to warm up quickly, and TBH I think the oil pressure is higher at fast-idle anyway so the oil gets there a lot faster.  The initial start-up relies on the oil to resist draining back to the sump when you last switched off.

The MAF is a hot-wire device, it uses a by-pass orifice to measure a callibrated percentage of the air flow.  It works using a wheatstone's bridge where 2 of the resitors are fixed, one is a reference thermistor for ambient air temp and the last is a hot-wire in the air stream.  the current heats the wire, the air cools it.  By comparing the cooling effect on the wire (the wheatstone's bridge) one could calclutate the mass air flow, not volumetric air flow as in the flapper EFi fitted to 3.5 angines.  I'n not sure if the MAF unit has it's own brain or not as there are 4 wires to it but I think it does.

Anyway, the Haynes manual list a series of checks for the hot-wire system inlcuding the MAF, I'll have a look for you.

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