The leads were made up by an auto electrician for me and replaced when it started missing as I thought it could be the leads. The only other thing I can think it could be the is maybe the BOV as this is an unknown type and make being on the car when I bought it and as my co2 readings are all over the place on tick over I don't know if this if faulty.
As for the exhuast and air filter they have already been changed for a cone filter and a 3 1/3 inch system straight through from the turbo. I have an intercooler fitted just need some pipe work to plumb it in now.

try putting a better earth on the coil. this has happened to me afew times

Thats good advice, i moved my coil as i found the standard posistion is a bit of a water trap from the top of the inner wing. and i added a second earth n touch wood i aint had anymore problems with it since:)

When I put the new coil I cleaned up where it mounts so I might try adding another earth and see what happens.

3 1.3" :eek: Thats the bigest bore i have heard of so far on a s12!:D

It's a tad on the noisy side it came with the car so it would of been rude not to use it, though I might change it for a 2 1/5 inch system if only to stop my windows vibrating when the cars cooling down.

Keep it and Put a performance straight though middle silencer in :)

Another question how easy is a T25 to fit? And if I fit one will the timing need adjusting at all? The reason I am asking is although I have a spare T2 there is a srapies near me with a couple of S13's with knackered engines in otherwise I'd be looking a fitting a DET.