E34 M50 Rough Runner / Poor Starting

[Toysr1]

Hello

Can anyone point me in the right direction please?

1995 2ltr 5 Series M50 engine, the engine starts but runs as though it's running on three or four cylinders, plugs are wet as though it's getting fuel o.k. checked for air leaks and can't find anything. I.C.V. is clean and free, air filter checked, no "maggots" on the coil packs when looked at in the dark.

When the car starts it is very lumpy and will rev but dies quickly, when it does cut out the two relays in the ECU box on the LHS of the engine (looking from the front) are both chatering until you switch the ignition off. What are these two (only two in the box) for? Any ideas on the problem please.

Thanks in advance.

[Guest DazH]

Hi Paul,

Sounds to me like a grounding issue with a relay problem twang...

Pull the relay and use a multimeter to do a resistance check maybe? Or just... replace them :)

Daz