the gauges work fine until i got WOT. when i do that, they both go to 0. im using a blox oil filter adapter and both gauges are stewart warner. i also had some cheap gauges hooked up on the oil adapter and they did this too. i assumed it was the cheap gauges so i bought the nice stewart warner ones. and they do it too. this is not normal is it?

 

I have heard of issues if the sending units aren't grounded properly.

 

hmmm. well its fine under all conditions except WOT. that could be it i guess. the sandwhich adapter isnt touching any metal since it uses a rubber gasket to seal it.