110k mileage. 1990 Acura Integra
I have been driving it about a month and would have done like 100 miles. About 70 miles ago I changed the engine oil. Lately it is raining in California. All of a sudden, within about 0.5mile of driving, Low Oil Pressure Warning Light came on and flickering.
All the fluid level is more than max level. Firestone might have put 5qt instead of 4qt.
What should I do?
Too much oil in the oil pan can cause the crankshaft lobes to whip the oil into a froth. Which contains air.
Oil pumps weren’t designed to pump air.
Bring it back!
Tester
You’re gonna need the oil pressure tested with another gauge. Most shops have their own calibrated gauge they can easily test it with. Presuming you aren’t hearing any weird noises, could be something as simple as a faulty oil pressure sensor. If you want to be extra cautious, don’t run the engine any more, tow it to a shop.
Thanks @Tester & @George_San_Jose1
I was driving in the drive way after a 0.5mile drive when I first noticed it.
I stopped it immediately.
Can I start car now to see if it comes back on? Is starting as bad as driving?
All you can do is start it, let it idle, and listen for any noises from the engine, and watch the oil light.
Tester
If the light doesn’t come back on can I drive to the shop 2-3 miles to have the oil reduced?
What is if there is no strange engine noise?
What is if the light doesn’t come on?
Why is it so bad to drive with this light on?
this happened to me once and it was a bad oil sensor so I bought one and screwed it into the block and problem went away.
How did you figure it was the bad oil sensor - troubleshooting doesn’t seems easy especially if you can not drive the car.
What is so different in driving vs letting the car to idle under these conditions?
If you replace the sender before driving again (often pretty cheap and easy - it’s usually near the oil filter) then start the car: if the oil light is not on and doesn’t come on (except when the dash lights come on just before you start the engine) while driving, you are OK.
But overfilled oil needs to be addressed before you do much driving. I’d ask the shop to come extract it via the dipstick hole. Then see about the sensor and indicator light.
any thing is really wrong like low oil pressure you will hear a knocking noise 
This is at idle?
I started the car and let it idle - after about 2 mins, the engine oil light came on. So I turned it off. I need to tow the car to adjust the oil level.
So the light does come on at idle.
Did you check the oil level?
If it is low, add oil and re-test?
It was checked. and it may be a quart over-filled.
Tester
What is “Switch” Vs “Sender”?
Which one is worth changing without diagnosing?
Oil pressure switch = the vehicle has an oil light.
Oil pressure sender = the vehicle has an oil pressure gauge.
Tester
Thanks - mine has a light only.
So it would be the switch correct?
Yep.
Tester
Had the car towed and re-did the oil/filter.
M/c demonstrated to me that even with 3qts of oil the “engine oil light” came on (its very dull though).
He put 4 qts and the (dull) “engine oil light” was on. As I drove home 3-4 miles, it disappeared. Then started the engine again it came on but disappears as I start to drive.
The light is not bright red as you see when you first turn the key (without the engine running).