Hey, I've been driving the Stang recently since I'm home for a bit and noticed that the oil pressure hangs around the O in Oil while at idle than climbs to nearly past the L when driving (doesn't matter rpm, just climbs) then drops back down to the O while at a light. I don't really remember it being like this, but last time I drove was in December. It's a 66 289 4bbl with original gauges, which I know aren't accurate. With the planes I fly, they tell you what to look for in fluctuating oil pressure or if it's out of limits, wish cars would do the same. Thanks for any help.
This is a total guess, but do you have enough oil? Maybe you are driving around oil starved/low... but when things settle out at the light the pressure goes back to "normal". Just a guess.
I checked the oil and it's good, just got it changed not too long ago. It's getting better now that I'm driving it more often. Gotta love old cars, real finicky sometimes. When I haven't driven it for awhile the first couple drives are a little rough but things smooth out with a regular cruise.
get mechanical oil pressure gauge, cost some 10-20 bucks in pepboys or similar store if it still reads inconsistently try using harder, non-synthetic oil like 10w40 or 20w50 before digging deeper in the engine (bearings, oil pump)
