I am installing a VDO oil pressure gauge. I have it all installed, including the VDO sending unit with the "warning contact" that allows connection of the original warning light. The gauge works great, but the warning light comes on when the gauge reads about 50 PSI. This is as the rpm's reach 2500 or so. The warning light turns off when the engine goes back down to idle which is about 30 PSI.

Here's the ugly part. This didn't happen in my first short test. The warning light wire had a female connector to attach to the original sending unit. I cliped this off, stipped another quarter inch of wire and crimped on a spade connector to attach it to the new sending unit. My first test was with the female connector pinched in the sending unit and it worked fine. With the spade connector attached, it behaves this strange way.
My question is, can shortening the wire by a quarter of an inch cause the warning light to malfunction? Thanks for any thoughts.

Rich L.
99 1.8TAQMS