Sooooo, my truck was havin cold start problems. glow plugs were shot. replaced them and harnesses at the same time. prior to this my oil pressure gauge was jumpin all over the place and truck didnt seem to have as much power or acceleration. after i changed the plugs and harnesses this first thing i noticed( after it fired rite up in 25 degree weather) was the fact that the oil pressure gauge was behavin like its supposed to. Truck runs better, smoother. i start it up this am and what do i see? gauge is havin a seizure again. i know these gauges arent the most accurate, but the difference when its behavin vs not is noticable. is there a correlation between the uvch and oil pressure? Maybe somethin came loose?