ok so im brand new to this site but not to hondas my question is on my 91 civic si hatch what is the part on the fuel tank front left corner is it emission stuff and do i need it? when i dropped the tank to fix walbro half tank bs because of there bag that sticks straight up (got the fix and dont use the crx stock bag if ur running the 255 it wont keep up i got the fix hmu if u need help on that) i noticed a humming noise coming from that part when pressure applied to tank any ideas?

 

Its the evaporative emissions stuff that feeds the charcoal cannister and the evap stuff on the manifold. Take it off and you usually have fuel vapor smells in the car in my experience.

 

Is it supposed to make a humming sound when pressure is applied to the tank or does that mean it's bad?

 

would have to check a service manual on that. i know they are diaphragm type valves that relase the pressure into the lines but i have never had to mess with the obd0 systems since they never throw a code...

 

Ok last thing I'm running obd1 on a itr type r I can just get rid of the thing and cap it off that way no gas smells right ?