Have a coupe turbo, z20let, when i bought it, it had a baileys dump valve fitted, then a mate of mine fitted a 1 way valve said it ran better etc.
it ran fine,
then just the other week i had water pump & timing belt done, wit new rocker cover gasket and other wee bits done,
i treated mysefl to a collins dump valve,
Occasionally it idles very low
occasionally cuts out say if i pull to a stop at a junction or something!
Occasionally it flashes dash warning lights up, like traction control, battery, service light and engine management
Now this is occasionally as even this morning it seemed absolutly fine
Also the collins dv has liek a second or 2 delay before u hear the wooosht noise
Any help be most helpful
Any1 know why this is