ok so I swapped existing coil packs and spark plugs over and still miss fire on cylinder 3 so its not spark plugs or coil packs . I swapped 2 and 3 over and also 6 and 7 incase I had the wrong cylinder numbers ….anyone got a suggestion for plan C ….?

an injector sticking on a car that sits unused 5 days every week?

a thought just came back to me....when I bought the car and got it checked over by a merc specialist....they listed the battery as needing replaced although ive had no problems with dim lights or slow cranking over .ive just came across an article online saying an under performing battery can trigger faults.....anyone experienced that sort of thing? is that right?