1999 e320 code p0446

[Jim teacher]

I have 1999 e320 it has a code p0446 and p0450. The purge canister valve has been replaced . The voltage to the valve and the tank pressure valve is b+ voltage. 2 wires to the pressure valve had excessive resistance and I overplayed the wires. On the second start it will after 15 seconds put on the check engine light. The purge solinoid has also been replaced . any ideas?

[97 SL320]

Do you have a Mercedes specific description of the codes? Much info can be lifted from the detailed description.

How high resistance for the wires? I'd be looking for animal or similar damage to the wires.

[Jim teacher]

The 2 wires had 36 ohms and 50 ohms resistance they were the wires from the tank pressure unit the wire colors were violet and gray and brown and green. I am thinking it is a dead short maybe in the tank unit. I tested all the other wires to the canister purge valve they were OK. I was trying to find out which line at the canister purge has vacuum.