Can anyone help I have a sierra 2lt dohc 8v it has a vege recon engine. I can get it running on four cylinders when the choke is on but once it gets warm it goes onto three cylinders. I have fitted an exchange weber carburettor, new spark plugs, new plug leads,rotor arm and checked all the compressions which are spot on but still it is on three cylinders. I also seem to have trouble setting the co with my meter. Has anyone any idea or experience of this problem as I have spent five or six days trying to sort it out.