MG Car Repair: Car still runs slightly after ignition turned off, charcoal canister, octane

Question
Hi Howard. It kinda chugs for about 3-5 seconds after I've turned the ignition off. This happens everytime I've been out in it.

Answer
Hi Jo, It depends what year MG this is. If it is an MG with a charcoal canister, it is suppose to have an anti run-on valve next to the canister. The anti run on valve supplies a vacuum to the carb float chamber to shut off the fuel from the jet when the ignition is switched off.

If it is an older MG with dual SU carbs you either have the ignition timing set wrong or your idle is set too high or you are using low grade gas when you are suppose to be using 93 octane. Or your engine is over heating.

Let me know,
Howard