My 1300 xflow in my MK1 Fiesta won't run right, i've replaced the coil, dizzy, plugs and leads to try and solve the issue but no luck, The problem is this, i've got all the leads in the correct firing order, managed to get the timing set because the car will tick over, but when i rev the engine, i'm getting popping/banging from the exhaust and the odd flame out the carb, it's running like it's badly out of time or the leads were all on the wrong way, but they're not. Not sure what to look at next, this engine was running fine at one point.