Evap Filter 7DO201849B
开云体育On the vent?side of the evap system in my 2000 EVC, there is a mysterious cylinder with part number (possibly VDO 201 849 B ? It's hard to read the first letter). ? One side of it plugs into the left frame rail, and the other side goes to a T which then goes to the LDP??(Leak Detection Pump) and N115 evap vent valve. ? I found a diagram which (for the 2001 models) which calls it an Air Filter for Diagnostic PumpIt probably filters the incoming air to the evap vapor system (when air is flowing in) also as a way to deflect overflow vapors out of sight (by "hiding" them in the left frame of the van) when fumes are flowing out. What if this filter is?partially?clogged? 1. When the N80 purges vapor from the canister, some clean air will enter the system, and vapor would still flow through, but at a lower amount. ?This is likely enough to pass the N80 tests, so you don't get a CEL. 2. When the LDP runs a test, some air can still pass, so the leak down tests should pass. ?No CEL 3. However, on a hot & high day, the flow restriction could prevent the Evap system from purging enough vapors, and as a result the tank pressure would keep climbing, leading to the symptoms we are having. As a test, I disconnected the vent?hose from the canister,?and tried blowing and sucking. ?I'm able to get air going through the filter, but it does feel as if there's a moderate amount of restriction. ? The part is NLA, of course. If the only function is to make sure the LDP is sucking clean air when it runs a test, it seems like replacing this with a small air filter would be a good replacement. Thoughts? Mike |