No doubt about it, your engine is overheating.

Dear Car Talk | Jan 01, 1996
Dear Tom and Ray:
Marilynn
RAY: I'm going to suggest another repair shop, Marilynn. And I'm also going to take a guess at what the problem is.
TOM: A guess? As opposed to what?
RAY: A wild guess! I'm going to guess that your oil problem is a symptom of something else. And what I believe it's a symptom of is a bad cooling fan.
TOM: Whoa! A veritable stab in the dark!
RAY: Well, it may not be the cooling fan, Marilynn, but something is causing your car to overheat. When the engine overheats, the oil gets very thin. And when it gets too thin, it can't create sufficient pressure. That's why the oil warning buzzer goes off. And the overheating is what'sprobably causing the car to stall, too.
TOM: By the time you get it restarted, and get it to your dealer, it's not overheating anymore and the oil pressure is OK. So your dealer does a five minute oil pressure test and gives you the "mechanic's shrug."
RAY: I'd ask a more interested mechanic to check for overheating. The overheating could be caused by a plugged radiator or a stuck thermostat, but since it happens when you're stuck in traffic, I'd put my money on an inoperative cooling fan.
Marilynn
RAY: I'm going to suggest another repair shop, Marilynn. And I'm also going to take a guess at what the problem is.
TOM: A guess? As opposed to what?
RAY: A wild guess! I'm going to guess that your oil problem is a symptom of something else. And what I believe it's a symptom of is a bad cooling fan.
TOM: Whoa! A veritable stab in the dark!
RAY: Well, it may not be the cooling fan, Marilynn, but something is causing your car to overheat. When the engine overheats, the oil gets very thin. And when it gets too thin, it can't create sufficient pressure. That's why the oil warning buzzer goes off. And the overheating is what'sprobably causing the car to stall, too.
TOM: By the time you get it restarted, and get it to your dealer, it's not overheating anymore and the oil pressure is OK. So your dealer does a five minute oil pressure test and gives you the "mechanic's shrug."
RAY: I'd ask a more interested mechanic to check for overheating. The overheating could be caused by a plugged radiator or a stuck thermostat, but since it happens when you're stuck in traffic, I'd put my money on an inoperative cooling fan.
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