Mysterious burning oil

I just bought a used car. I drove it about 250 miles on one trip and the engine seized without warning. The mechanic says that there were no signs of a leak and that I was likely burning oil. I had checked the oil before leaving for the trip and the stick was dry so I put in 4-5 quarts before I hit the road. I checked the stick and it was full when I left. Is it possible to burn that much oil that quickly and see no signs? Is it possible that there was a leak and there’s no sign of it now that the engine won’t turn and all the oil’s gone?

Yes, it’s very possible to burn that much oil in 250 miles, especially if it had already been being driven around with no oil to begin with. I’ll bet your cylinders are world-record scored.

I’d recommend learning two important lessons and letting the cost of this be considered the expense of an education:

  1. get any used car checked out thoroughly before buying
  2. always check fluids regularly and incessantly on any newly purchased car. On a used car that’d be every stop you make.
  3. even after filling the oil, check it incessantly, especially if it was dry when you filled it.

Okay, that’s three lessons.

How many miles had you put on the car before the 250 mile trip?

Is it possible to burn that much oil and not know it though? I’m not so oblivious to not notice a huge cloud of smoke behind my car.

Also, I had it checked by a mechanic before making the trip and he said it was A-OK.

I had only driven the car about 70-80 miles before the 250 mile trip.

Yes. it is possible. You’ve proven that. Much of the oil smoke could have ended up coating the insides of the cat converter and the rest dissipated into the air behind you too thin to notice in the mirror.

You drove the car 70 to 80 miles without checking the oil. When you checked it just before the trip it was bone dry. The damage had already been done. Its bone dry condition before your trip should have been a “heads up” to you that something was amiss.

When the shop checked it prior to the trip he probably focused on safety issues like brakes, chassis and tires. Since you’d just topped off the oil, he probably just checked the stick and never gave it another thought. Nobody checking a car in preparation for a trip is going to do things like a compression check unless they have some specific reason to do so.

Thanks for the quick reply. Very helpful.

" I had checked the oil before leaving for the trip and the stick was dry so I put in 4-5 quarts before I hit the road."

Clue #1: Something was VERY wrong…Now, lets talk about the oil-pressure warning light that must have come on but you somehow failed to notice…

What model year is the Altima and how many miles on it…?

2002 with 111000 miles.
The oil light came on very briefly and I checked it very soon after the light came on.

I had previously had my oil changed and the guys forgot to put oil back in and that’s what I think happened again here. The oil light on this car just didn’t come on as fast as on the other car that I had. On that car, as soon as I drove out of the oil change place, the light was on. This one, I was driving for a few days and about 80 miles or so before the light came on.

Ok - lesson 4 to continue w/ mointainbike’s list - do not use quickie oil change places or anything like them. Find regular, local shops with good reputations. I would go try to hang this on the oil change place. Hopefully you kept a record of what went on.

Forget mechanical solutions to your problem. You say you bought a used car and it seized.
I believe your mechanic that there was no leak.
But have you read your question? You added 4-5 quarts of oil before you hit the road? Really? Because that’s pretty much all the oil your car can hold. And I doubt any engine that requires as few as even as four quarts can run for even 20 seconds with a single quart.

If there was no oil showing on the stick before you left then you were doomed from the get-go and never should have left the driveway.

You may not have seen smoke because the converters and exhaust system is catching most of it.
Unless this mechanic performed a compression check then he has no idea if it’s an oil burner or not and definitely should not pronounce something A-OK.

Another thought:
Whenever fluids are changed, including oil, always check the fluid levels before starting the engine to leave the shop. Check the levels and look for leaks.

That also applies to any other work that’s visually verifiable.

I do my own work and I even double and triple check my OWN work. Driving off without a key fluid is just too costly to risk.

If you added four to five quarts, the engine was already damaged, probably badly, before you left. Were you not aware of this?

DCdisaster…

The Nissan QR25DE engine in the 2002 Altima and Sentra is NOTORIOUS for drinking oil. The 2002 year model was a brand new design for that engine, and apparently not all the kinks had been ironed out before it was released to the public. The internet is filled with stories about it.
IIRC there is a recall/extended warranty from Nissan on these engines, but I could be wrong. I guess it is time for you to research this. Start by taking your VIN # to your nearest Nissan Dealer and ask to see if you qualify for any free work. Or, you could try and take back this car where you bought it from and ask for your money back.

I do not mean to come accross as an azz, but I must say this:
You should have done a bit of research before buying this car. In this day and age of the ALLMIGHTY InterNet, where tons of info are at ones fingertips, you have absolutely no excuse. In general when purchasing a used car it is always best to do some research BEFORE plunking down you hard earned dollars.

Best of luck.