jpl77
01-25-2015, 02:53 PM
I have a code 250 or P0440 of function check, tank ventilation, after I installed a new tank purge valve.
The vehicle is a 2002 BMW 530i.
The fuel filler cap is relative new, and has been swapped with another good one for test, too. The
purge valve hose could hold an vacuum, thus no leak.
I could not hold a canister vacuum from purge valve and suspect there is a vacuum leak some where. I
could blow air from the purge valve hose to canister and the air came out from the leak detection
pump filter.
Isn't there a canister vent valve inside to hold this vacuum? It seems the air could flow between
canister 3 in/out holes freely. Is there a valve inside stay open?
It seems the leak detection pump allow fresh air come in all the time, as a normal. Does this
cause a leak? is there a valve to allow one way air flow (in the filter)? When I tested it with soap
bubble and blow air into this pump, bubbles would come out from the middle housing seal. Is this bad?
thank you,
JP
The vehicle is a 2002 BMW 530i.
The fuel filler cap is relative new, and has been swapped with another good one for test, too. The
purge valve hose could hold an vacuum, thus no leak.
I could not hold a canister vacuum from purge valve and suspect there is a vacuum leak some where. I
could blow air from the purge valve hose to canister and the air came out from the leak detection
pump filter.
Isn't there a canister vent valve inside to hold this vacuum? It seems the air could flow between
canister 3 in/out holes freely. Is there a valve inside stay open?
It seems the leak detection pump allow fresh air come in all the time, as a normal. Does this
cause a leak? is there a valve to allow one way air flow (in the filter)? When I tested it with soap
bubble and blow air into this pump, bubbles would come out from the middle housing seal. Is this bad?
thank you,
JP