so i decided to hook up a catch can today. problem is since ive hooked it up, it seems my fuel consumption has gone through the roof according to the ecu. it used to say 0mpg during idle but now it says like 6l per 100km when ideling. it goes down as i slow down but when im almost just at idle speed (automatic) it goes back up to 6l per 100km. im really confused. and now just under normal acceleration it goes to 20l per hundred km and stays there until i reach speed.
maybe i hooked it up wrong? i followed this thread to find where the pcv is... and i went a honda freak to ask if this was right and he said yes..it was like a short 20cm pipe that looped from what i was told was the pcv to the intake manifold just 10cm above the pcv. the pcv was yellow?
https://www.fitfreak.net/forums/2nd-...-question.html

any help appreciated cheers

 

Can't tell where you hooked it to from your description perhaps you can take a picture.
You should have no difference in mpg unless you hooked it up completely wrong and perhaps you are allowing to much unmetered air into intake. That only way I see it having such an effect and you would notice other symptoms I'd think like rough idle and probly a cel.
The pipe you want is mounted I front of the throttle body and is welded onto a bracket with some other lines. Hard to explain as there are lots of hoses in this area so a picture is your best bet.