How I almost oil-starved an engine to death

After work yesterday, I was driving my Samurai into a parking lot, and just as I came to a stop and the engine fell to idle revs the oil pressure warning light flickered on briefly. I figured maybe this engine's more worn than I realized.

Then the next morning, on 3 different occasions it flickered on for about half a second at over 2krpm under engine braking but it only took the first for me to to know that E36 M3 Just Got Real.

Last time I checked the oil level was about a month ago and it was overfull by at least 1/4 quart (mechanic who swapped the engine overfilled it). It didn't make any sense for this engine to be having oil starvation, it's run fine for many minutes at a time at angles you wouldn't expect a wet-sumped engine to survive at for more than a few seconds. So as I approached a steep downhill I did a little experiment, I put the car in neutral and let it sit at idle revs. Soon after I began the descent the oil light flickered on again and I shut the engine off. Now I knew it was oil starving when gravity was coming from the front somehow.

So when I was headed out to lunch, I got some paper towels and checked the oil level. Dipstick came back dry I dumped a full quart of spare oil I had into it. Still dry. WTF? Maybe it was taking forever to drain back, anyway I had things to do so I drove off. I tried to drive it gently but I didn't get any more OP warnings.

At lunch I bought two more quarts of oil, I was in the store for a good 5+ minutes so I figured the oil must have drained back by now. Dipstick's still dry. I dump a full quart in again. Now it's 1/4 way up.

This engine takes about 3.5 quarts, and it didn't complain until it got down to about 3/4 of a quart

Where that oil went is still a mystery. I've had engines that smoked a lot and had leaks that didn't lose oil anywhere near this fast, and this one has little to no smoke and no drips I've noticed. There is a lot going through its crude crankcase ventilation system (an open port on the valve cover that's connected to the airbox post-filter) but I don't think that can explain it.

Point is, don't assume an engine isn't making oil disappear.

Now look at the shape of that oil pan, I bet you can guess which end faces backwards:

Amazing that the engine runs just fine pointed almost straight at the ground.

My first car was a Corolla with a 3TC. Oil light flicker under braking was the official indicator to add more oil. We sold it at 289k abused miles and it rand for years after that. It may still be running for all I know.

ultraclyde wrote: My first car was a Corolla with a 3TC. Oil light flicker under braking was the official indicator to add more oil. We sold it at 289k abused miles and it rand for years after that. It may still be running for all I know.

Change Corolla to K-car and braking to hard left turns and the story is the same. Still a mystery how that car lived.

The old Accent went down to under a quart a few times. Car wouldn't burn a drop of oil for 4k miles. by 6k it would burn a quart. 6.5k another. 7 another quart. Wife brought it home a few times asking about hte red genie lamp that comes on when she turns or stops.

Old Chevy Scottsdale I had was so low on oil a couple times I saw the oil pressure needle bounce as it "slurped" up what it could.

One time I took the next exit only to get stuck at a light. the valve-train started to let me know that "E36 M3 was gettin real, quick".

she had a known "quart-per-gallon" habit though.

Pretty much exactly the same thing happened on my friend's Mini. Except on her car you can't even read the damn dipstick because its a giant spring and holds the oil that gets splashed on it.

Found another dipstick from another car that fit and was about the same length.. put 4 quarts in and it finally showed up on the stick. The oil had been changed 3 or 4 months before. Oil light came on during a long downhill slope.

0.5 quarts of oil left in the sump on a turbo car.. not good.

My 06 Magnum turned itself off and beeped incessantly if you ran it that low on oil. That's the only reason my partner didnt blow it up..

Opposite story:

My buddy had a Trabant 1.1l.

He swore it had a leak even though I could never find one. Well one day he calls me and says "It finally let go. I came out this morning to a pool of oil under my car"

No noises, no knocking, just oil

So I go over and check his dip stick and it was FULL! I'm talking to the top of the valve cover type of "full".

It turns out the idiot never bothered to see if he was actually losing oil. He just assumed it was (because Trabant) and added a quart at whatever random interval he deemed necessary. All without ever touching the dip stick.

I tell ya. Other people's children...

My friend from another country just bought a '99 Camry. We checked the oil, and there was nothing on the dipstick. 2.5 qts later, it was full. Total capacity = 3.8qts. The sad thing was that a shop had just checked it over and said it needed new tires, a new wheel stud, and a battery. I told him never to take it to the place that did the post-purchase inspection again!

20 odd years ago, I had a recent immigrant type lady bring her Nissan Micra in for an oil change. I pulled the plug, and nothing came out. Did I pull the right plug? Yes. I stuck a screwdriver up the hole- no clog... Those little 1200 Micras had pretty sturdy cranks...

I changed the filter, filled it up, and suggested she needed to check the oil more often. I presume the red light on the dash was her "Change Oil Now" warning.

Does pouring five brand new bottles of oil straight through the engine into the old oil sitting in a pan under the engine, and wondering why there's a big puddle under the car count?

No? Good, then I didn't do that...

we get people coming into work often for oil changes because they think the low oil light is a service indicator. record so far was a guy with 21,000 miles on his oil change. that 3.8 sounded horrible coming in.

You know you're dealing with a bike engined car when your "starved of oil" story is quickly followed by an "engine parts where they shouldn't be" story.

In reply to dropstep:

Yes, in my 1 1/2 yrs. as a mechanic I quickly learned that a substantial percentage of car owners think the oil pressure light means either "hey, throw a quart in there and then don't worry about it until I come on again" or "go to the shop, time for some oil or something!"

I should have been tipped off about this by the fact that every few months, as I'm checking the oil while getting gas, someone walks up and asks what's wrong with the car, or if I need them to call a tow truck for me. This was more common with my '89 4Runner, but still happens occasionally with my '07 Fit.

Streetwiseguy wrote: 20 odd years ago, I had a recent immigrant type lady bring her Nissan Micra in for an oil change. I pulled the plug, and nothing came out. Did I pull the right plug? Yes. I stuck a screwdriver up the hole- no clog... Those little 1200 Micras had pretty sturdy cranks...

Nissan makes some pretty tough engines, at least in times past.

I work in the fork lift industry, and Nissan H-20/25 series engines are common. More than once I have found one completely dry. None of them died from it. They can even go without coolant for a surprisingly long time before the HG fails. I had a service call on one once that was "running hot". When I got there it was being used to load trucks all morning. The temp gauge wasn't working because the Eire terminal on the sensor had melted. The engine was rattling a bit too. 4 qts of oil, and a gallon and a half of coolant, and all was well. The engine was so hot that the coolant flashed to steam when it hit the insides of the block! That machine was still running OK for many years after that incident.

Is this the right time to point out how much I hate oil lights? A quality oil pressure guage is so much more practical and has saved my butt (and my engine as well) on more than one occasion.

dropstep wrote: we get people coming into work often for oil changes because they think the low oil light is a service indicator. record so far was a guy with 21,000 miles on his oil change. that 3.8 sounded horrible coming in.

I know someone with a new Ford who has 31k on the same oil.

He figures, well it's out of warranty anyway, so it's a science experiment now.

I'll do that science experiment on my old, low-stressed Audi engine. I wouldn't try it on a new direct-injected engine.

ncjay wrote: Is this the right time to point out how much I hate oil lights? A quality oil pressure guage is so much more practical and has saved my butt (and my engine as well) on more than one occasion.

Meh, I think if you give people a real gauge most will ignore it completely, some will panic every time it moves, and a tiny fraction will know how to use it. This is why new car coolant temp gauges basically just show "cold," "normal," and "hot." Really, for most cars we just need two big, annoying lights, an orange one that says "take me to a shop soon" and a red one that says "stop driving and call a tow truck."

ShadowSix wrote:

ncjay wrote: Is this the right time to point out how much I hate oil lights? A quality oil pressure guage is so much more practical and has saved my butt (and my engine as well) on more than one occasion.

Meh, I think if you give people a real gauge most will ignore it completely, some will panic every time it moves, and a tiny fraction will know how to use it. This is why new car coolant temp gauges basically just show "cold," "normal," and "hot." Really, for most cars we just need two big, annoying lights, an orange one that says "take me to a shop soon" and a red one that says "stop driving and call a tow truck."

Yep.