i have fitted a 195 bhp powerchip ofab and Beige injectors and a escort cosworth fuel pump and a -31 but the car will not idle properley.But when i put the standard frst fuel pump back on it idles well i have not got a clue why please help

 

I expect your fuel pressure regualtor needs adjusting as the cossie pump will be delivering the fuel faster and at a higher pressure.

Chances are its over- fuelling at idle

 

where is the fuel pressure regualtor placed in the engine bay

 

as you look from the front it WILL be at the right hand side at the end of fuel rail silver/grey in colour it may still have the seal in the middle(will have to remove that and use an allen key to adjust)

 

thanks