A mate has a s2 rst it is missfiring and making a very load banging noise could this be a head gaskget gone anyone help

 

when u say banging noise do u mean like a backfiring sound or loud poping, sounds more like the distributor has packed up 2 me!

 

has he got the leads in the right order?

 

might be overboosting

 

Its like its got a back fire but when it does it its like a shoot gun going off
K1nfscossie , You my be right it is running high boost (i think)
Thanks for your info if you mite know of any more things that could course this would be more then welcome to here them (my buy it for spares for my s1) Thank Alan