Ok, I bought this mustang as a prodject car from someone, and the had put a 302 in it, rebuilt. The only problem is, its a motor with the old firing order, which is not right for the a9l computer. So, I swiched the fuel injectors and plugs around to match the firing order, and with luck it works for the most part. Before it was missing on 3,4,5,7. Which are the cylinders that are differnet on the firing order. So anyways now I am only missing on 3 and four now, any suggestion on why the aren't firing?