98 C230 P0450 code?
I figure it may be one of the following:
-fuel tank pressure sensor (in the fuel tank)
-evaporative vapor pressure sensor? (I think this is on the intake manifold)
-charcoal canister shut off valve (solenoid?)
-fuel tank evaporative control purge valve (haven't found this yet)
PS - it's not the gas cap.
After checking the fuel tank pressure sensor signal at the ECM and at the Fuel Tank it looks like it's bad. Min voltage on the signal wire should be 0.1V and higher with atmospheric pressure in the tank, i.e. gas cap removed.
The fuel tank pressure sensor connector is located on the under side of the passenger side fuel tank, under car, in front of rear axle, remove cover with 3 bolts. It is inside the tank and part of the passenger side fuel sending unit.
There are 3 wires, Red/Green (5v supply from ECM), Brown/Gray (ground from ECM), Gray/Violet (signal from sensor, 0.1-5V).
If anyone has a similar problem and needs pics I'll post them.
http://www.europartsdirect.com/epc-items.asp




