A few times recently when I start up my 89' 302, on a below freezing morning, the engine fires up as always but the oil pressure gauge doesn't budge. There is no change in sound or idle to the engine. After a couple minutes I shut down and restart then the gauge functions fine.

My question is if the cold could affect the gauge/wiring or is it likely a mechanical issue? How would I test other than running a mechanical gauge?

 

Mine does that, the dash gage doesn't move, but my aftermarket one reads just fine. Them all of a sudden the dash will read.
What weight oil are you running?

 

Off-hand i believe I'm running 5W, whichever is required. You reccomend anything particulate for cold NE Ohio winters?

Glad to hear it's likely the gauge. I figure other than a complete mechanical failure with the oil pump drive shaft or oil passage obstruction (unlikely), it's just a tire gauge/wiring.

Mechanical gauge will go in with my donor for just this situation.

 

if you don't hear anything then its the gauge. the electric senders, especially aftermarket junk replacements, dont like to work in cold starts.

 

doubpost....

 

I run Rotella 5w40 in the winter and 15w40 in the summer (high mileage and low pressure issues) so 5w30 is what's recommended just give it a few minutes to warm up before driving off and you'll be fine.