Gah sorry! I knew I was forgetting to add something, but it's a 88 tbi auto 700r4. it ran good before It started backfiring, is it possible that maybe the ignition module in the dist could have gotten shorted or maybe the plugs? Tested vacuum pressure and it seems OK haven't looked at timing, also it runs good and don't miss at idle or when cruising, could be possible it jumped time a little? also should have mentioned this when it does do the backfire, it will do it a few times then after that it won't when I go wot,