I have a VDO guage with a tubular sensor connected to a diesel fuel tank (all about 33 years old), the gauge was going from empty to showing 1/2 full erratically, i took the sensor out and cleaned the tube shook the assembly and reassembled to find the guage is not working at all, i checked with our local VDO agent and says you have to replace the sensor $480 approx or buy an WEMA sensor and matching guage for about $280, has anyone got any thoughts?