hi there i have a prolem with my s1 sometimes when i start it, it will run fine other times it will sound like it running on 3 cylinders and cuts out very unpredictable, could it be an ecu problem? censors? bad earths? any help would be great. its had new leads, plugs,dizzy cap,rotor arm,coil thaks matt

 

now doing it all the time could it be an over fueling problem? could over fueling make it run this bad?

 

more than likely to be the metering unit!

 

Does it do it any specific time?

I.E when cold?