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And with regards to the original post, which I hope is already fixed (just posting all this because Im new and have been doing evap for 15 years all makes but porsche lately) since this had a pump sense circuit in addition to large leak...Id generally start with pump diagnostics (does it turn on/pump when commanded?) and is it getting vacuum (the small line). If its getting vacuum (remove the small line at the pump when running) and it cant see it...pump is bad. If there is a problem with the pumps diaphragm leaking internally so it never moves despite vacuum...same issue, bad pump. If its pumping like a champ...but the vent is plugged solid as loren said, it will still see itself as bad. (most cars dont measure pressure for anything by the tank itself, they dont know how much PRESSURE anywhere else in the system, they see the CHANGE as indication that it worked. pressure change on/off switches are much cheaper to make than pressure measurement sensors that can record exact amounts). TYPICALLY, in most diagnostics post 2000, when a code uses the word CIRCUIT, you are chasing something electrical that isnt changing as expected or isnt showing proper voltage/ground as expected even when not active. unplugged stuff sets a CIRCUIT CODE.Shorted wires set CIRCUIT codes. leaking hoses set LEAK codes or PRESSURE codes. RANGE codes are the factorys way of saying IT COULD BE EITHER, SINCE A LEAK WILL SHOW SENSOR VOLTAGE THAT ISNT WHERE WE WANT IT, BUT ISNT SHORTED....but they like to hedge so they say RANGE. It means its likely electrical, but dont rule out a leak entirely and look at the electrical values if you have a tool to do so. So if you get a code that says PURGE CONTROL CIRCUIT, or LDP CIRCUIT, the 1st thing I check is the component is plugged in, and the wires going to it arent broken down or oil soaked. IF they look good, most solenoids are 2 wires, 1 a constant hot of 12v, the other a switched ground from the computer to turn it on or pulse it on rapidly to control flow. Evap solenoids almost always are pulsed...hence why they CLICK when they are working...they dont stay open or closed because that is uncontrolled flow. By pulsing at different amounts, they can open it 50% of the tyme or 70% or 20% and regulate flow. If the circuits function, and have power and ground (on or pulsed), then start checking for leaks as described above. It will be there. Also be aware, you can set circuit codes quite easily while testing. Unplug anything that is constantly checked (most components on newer cars) and check codes immediately...code is instant...even if you plugged it in 1 second later and its reconnected. Just clear the codes and if the code comes back instantly, its broken internally, bad wiring, or bad computer. circuits are constant...they are plugged in and work. Or they set codes.