I have been driving my wife to and from work in the 99 A4 Quattro Auto 1.8L. After about a hour drive on the freeway it is into stop and go traffic.

All is fine...I pick her up and back into the stop and go traffic...the red Oil Light beeps and flashes for a minute. When I get un-stuck from traffic, check the oil level...add a half quart...tell the wife the world isn't crashing down and drive home...no issues.

Next day...drive around all day...no issues. Pick her up late in the day...into the stop and start traffic...BEEP off goes the Oil Light again. The light beeps, flashes for a minute and turn off...5 minutes later...in the traffic jam it starts again...get up to freeway speed and all seems to be normal.

Any thoughts out there?

 

https://www.audiforums.com/forum/sho...d.php?t=164370
Sticky at the top of the page, 1.8T engine suffer from sludge. Audi had a TSB for it that covered the repair but your car is older than 8 years, so you need to fix it yourself.
Stop driving it until you can get these parts installed, you can do MAJOR damage to the internals with low oil pressure.

 

I assume that this issue is different from the yellow "Check Engine Oil Level" light?