hey gang

having running issues with the zetec engine i built, normally starts fine, but recently it will struggle to start, when it is running it shudders and fights like its going to stall and the exhaust is sounding like a missfire

i have changed crank sensor, cam sensor, coilpack, maf makes it run worse so is unplugged, lambda unpluged makes no difference iscv unplugged makes the car stall so thats working fine... timing has been checked and is all good, used pin and bar and flywheel locking tool

also checked for air leaks and cant seem to find any, but getting a hiss around the inlet area, only other thing i can think of is the crank case valve, i heard that can cause rough idle if blocked

also what colour injectors should be on the 1.8 got HO inlet and looks like black injectors, i'm wondering if they been changed as the engine came with the black plastic type inlet with brown injectors

any help would be awesome as i'm gonna set fire to it otherwise... not even gonna bother trying to sell it, its wound me up so much the last couple days, i would love to see 1K of engine rebuild burn in hell