Oil Pressure Bouncing Back And Forth

[Sigmawess]

I noticed when I started my truck my check engine light came on. In park the oil pressure guage bounced back and forth between 20-30 im guessing. When I drive it stabilizes at 40. What is causing this and is it normal. Ive never noticed before. Is this why my check engine light is on?

[Sigmawess]

I noticed when I started my truck my check engine light came on. In park the oil pressure guage bounced back and forth between 20-30 im guessing. When I drive it stabilizes at 40. What is causing this and is it normal. Ive never noticed before. Is this why my check engine light is on?

 

Took my truck by autozone and the read my error code. It was evap switch or emmisions switch or something like that. Nothing crucial according to the dude at autozone. I was going to bring my truck in this week but the light came off. I figure it was loose wire or something like that. Should I take it in anyway?

[Draenor]

It wouldnt hurt to get the oil sender checked. As for the evap DTC, it was probably related to the gas cap. Make sure it is on tight.