oil pressure

[serp]

good morning and happy new year ! i have a question on oil pressure. when idleing oil pressure reads about 15. when driving at any speed needle bounces left and right at 15. could gauge be bad ? and needle is bouncing due to vibration. i am going to check ground on gauge. do not want to drive until i can confirm pressure. have not done oil change yet. got truck 2 weeks ago. previous owner changed oil about 1 year ago 2000 mi.

 

[clinto]

Check the ground on that gauge, it shouldn't flop around like that due to vibration......... They have to be properly grounded. If you still get a low reading, put a mechanical gauge on it and verify real pressure.

 

[serp]

i put a ground wire on back of gauge. at idle it now reads about 40 .when i rev it it goes up to50 is that normal. also at idle how long should engine take to get up to normal temp.