So, Dirty or contaminated fuel.... possibly not a coincidence problem!
Your car I take it is a carburettor/ distributor type vehicle, a little more info on type and age would be good here though. Any upgrades such as electronic ignition etc.
Check points, rotor arm distributor cap condenser, in distributor. then plugs/ leads king lead and coil + connections.
Next, fuel filter, just change it. Now check spark at 2 plugs, if none, check spark holding king lead above the rotor arm contact and see if you get a spark jumping there to the top of the rotor arm when turning the engine over... wear rubber gloves! if not suspect a coil or low tension contact issue or duff rotor arm. If all is working here then come back to us and we can start to advise further re fuel, earths and the like! Start with car details.
Last edited by sewin; 15/08/25 09:56 AM. Reason: needed to add information