hey guys so I need help, my car is a turd and it's sending me crazy haha everything I write it's long and detailed please bare with me.
Ever since I bought the car it's been abit rough on idle but it comes and goes, cold starts it also acts like a pig, never dies, drives perfect but it's always been abit rough.
now at the time I put it down to the motor being..... well for lack of a better word shit. it had rod knock it wasn't happy and had like 5hp on a good day.
fast forward to me dropping a fresh b230fk in, new everything and the weird idle /roughness followed.
OK it's something that was on the car previously that got swapped over.
I have changed everything, different mafs, iac, coolant temp sensors, power stage, injectors ecus, ezks etc etc if it can be changed it has been.
at this point I've half given up /half going mad, depends what day you catch me on , it really annoys me and I need to know what the hell is going on.
recently I questioned myself and thought did I ever change the maf or is it the original one, I'm 98% sure it's been changed but maybe not.
so I've tried multiple different mafs with no change.
a couple nights ago I started googling as one does and stumbled upon @ALVO360 thread.
https://ozvolvo.org/discussion/11135/solved-b230et-lh2-4-rich-on-boost
holy crap is this the answer , he had the exact same issues , rough / misfire idle, rich as hell cold starts and super rich under boost , it was the fuel pressure reg...
Alex has been telling me to go an adjustable fuel reg for ages but i keep putting it off
this was a lightbulb moment the fuel reg has never been changed this must be it !!!!
so i just ran out the shed and got another fuel reg i had and slapped it in and started her up, it seemed a little smoother on idle but that could've been me being hopeful ill try again in the morning on a cold start .
so i took it for a quick test drive, AFRS were jumping around like crazy so i thought maybe i need to reset the ecu and start fresh, that seemed to settle the afrs alot more stable but its mega rich.
on idle its always perfect 14.6/7 , previously when you hit boost WOT it would taper down and settle around 10.2/3, light throttle /low boost it would drop down low 12s/ 11s , now its hitting 10.0 solid at like 30% throttle , WOT the same solid 10.0.
now im going to borrow a mates fuel reg and test that aswell just incase my spare was a dud but i need some more ideas if not.
what could cause rough idle, super rich cold starts and really rich at WOT .
even if we ignore the rough idle /misfire thing and focus on rich AFRS on full boost .
ive run multiple turbo ecus and ezks its always been the same , im currently running fuel and ignition chips from a bloke on turbobricks they did seem to make the car run smoother but AFRS have always been really low 10s at WOT .
Im running v70 white injectors with a 16T @15PSI
previously i was running xc70 brown injectors same thing, rich under boost
any ideas ?
sorry for the long post .....save me from this madness volvo peeps