rough on petrol fine on gas

[john_d]

my mondy run's rough on petrol but fine on gas, previously the engine smoked on start-up, this has now disappeared to be replaced by the "misfire", as its fine on gas we know the petrol side is at fault, I'm thinking it could be a faulty injector, any idea's how to check or idea's as to what else could cause the problem?

[DAKNIGHT_UK]

I would do the following (which worked on my vauxhall astra which wouldn't rev properly on petrol.

1. Try reddex in the fuel tank.
2. Change the fuel filter.
3. Clean the throttle body \ assembly with carb cleaner.
4. Replace spark plugs

Most petrol engines smoke on start up due to oil which seeps through the valve stem seals, thats pretty normal.