E30 Zone

hello!

i want to ask your advice regarding the following problem.
the engine is a m43b18 taken out from a '94 e36, 4cyl. timing chain version.
i recently failed my mot, on emissions problem. i checked for vacuum leaks, i couldn't find anything. the idle doesn't wonder, but it seems to be a bit low, around 700 rpm.

when checking the vacuum system i could see my icv valve stem would't move at all while poking it with a screwdriver. but with the engine running when i disconect the valve's plug, the engine revs up to about 1.500 rpm.

my question is, could the icv valve's faulty operation cause a emissions failure? or am i wasting time checking this?

thanks in advance!

Mike

if your idle is at 700 then thats fine so wont be stopping it get through the emmisions

i recently failed my mot, on emissions problem

Be specific!
CO
HC

And what age is the car, so we can tell what emissions standards it has to meet?

hello, sorry for not being specific earlier, it puts out about 0.65 CO
and it must be below 0.5 CO to pass the mot.
anyways, what could it be? could it be the icv? the cat?
lambda is 1

checked for vacums, but couldn't find any.
could it be the fuel filter? haven't checked that.
any ideas?
thanks!