i've just bought a 89' Sapphire Cosworth, currently running at 415bhp. It is misfiring from 4000rpm, i am going to change the leads and plugs. what is the correct gap for the plugs? also gonna check the fuel pump cos it might be starving the engine. also have a oil leak which looks like it is coming from the rear of the engine bay, the oil pressure is fine. gonna check the sump and gear box. if anyone can help it would be much appreciated.

Paul

 

Welcome to Cossie ownership - it's all fun and games from here.

Look at the Phase sensor in the dizzy, unless it's on a coil pack.

 

cheers mate will do!

 

Coilpack still uses the phase sensor, as you have just got the car I would do a mega service on it, not forgetting the fuel filter, and also a fuel pump and fan rewire if you want it to last, at this power it should have a 044 pump, if on std it could have problems, especially if the 20 odd years old one.
They suffer terribly from volt drop under load, and so run lean, the fan circuit is crap and most burn out, so a rewire is on the cards just for security.
As to the misfire, is it only under load ie if in say 3rd gear just letting it rev out over 4K is it ok ?
Plugs are a fave, as is the phase sensor wiring on the sensor itself, it breaks up and falls off, leading to shorting, but don't think for a minute it's this, something to look at though.
What plugs are you using, what CO is it running ?, what's the spec ecu chip ?
tabetha

 

gonna go through the car with a fine tooth comb, this weekend should have a big service complete. does anyone know of any good tuners in and around the newcastle upon tyne area?

 

Motoscope in northallerton have a half decent reputation mate, but it depends who you speak to, i know one or two that dont rate them at all.

 

Of course it does, silly me.

 

Think cozmeister's been on the wobbly water again!!
I saw your car today cozmeister, had someone nicked your usual spot ?
tabetha