Ok so ive got a bt escos which had a slight missfire when standard. So I fitted a group A coil and gapped the plugs to .7mm and all was well.However ive since fitted a full mongoose system and large cone filter and its now missing again. I changed the gap slightly to .65mm but even worse so should i be opening the gap up. Thanks Rob.

 

What plugs m8 ? How old are they ?

 

new plugs mate cant remember the make off the top of my head to be honest.

 

anyone

 

I'd try another set of plugs m8,especially if they're 071's.

 

there not 071s i no that much lol

 

The lead from coil to dizzy isn't running near the map sensor is it ?

 

It could well be ill have to look why can that affect it.

 

would this have this afect m8

 

Yeah,could be cps or phase sensor too.

 

hmmm ill try opening the gap and see what happens

 

Too small a gap is unlikely to be the problem, could just be one duff plug.
I would use some Iridium plugs as these require much less voltage to fire, and seem to resist fouling better too.
tabetha

 

They don't work well in all engines

Steve

 

When I made the gap smaller it wouldnt idle hardly at all made it much worse.