Automatic low-oil pressure shutdown mechanism

Recently a mechanic screwed up an oil change and all of the oil leaked out of my car before I even left the repair shop. The oil light came on about a mile after I left and then the car started making noises. The noises grew loader (they sounded horrific) and smoke started coming out from under the hood. The mechanic claims that there was no damage done to my engine because “these newer vehicles have a mechanism that shuts down the engine if the oil pressure is too low.” So does a 2002 Honda Civic have such a mechanism?

GM vehicles had this feature. Your Honda doesn’t. The mechanic owes you a new engine.

Tester

The oil light was on, but the engine was making a noises.

Ummmm, NO! This engine does not have an ‘Automatic Shut-down’ Feature, otherwise it would have shut down when the oil light went on, after all the oil dumped out.

“The noises grew loader (they sounded horrific) and smoke started coming out from under the hood.”

Why did you continue driving the car with 1) the oil light on, and 2) the engine making horrible sounds with the oil light on? I’m sorry to say that this engine is toast. The mechanic is snowing you to try to keep from buying you a replacement engine.

Just in case you need to hear it again - your engine is completely cooked and this shop owes you a new one. They should also apologize, not only for this whole mess, but then for being either dishonest or too foolish to be in business for giving you this nonsense.

Thanks for reply! I shut the car down as soon as the sounds got really loud and I figured out that they weren’t coming from the cars infront/behind me. I only made it a total of 5 miles. The mechanic was able to start the car after he put oil in it. If it was completely toast wouldn’t it not start up again?

But, does it run smoothly? Does it smoke out of the tailpipe? Does it accelerate as well as before? Is the gas mileage as good as before?

Even if it seems to drive OK, I doubt it will last much longer. Engines don’t like to run without oil, and the surfaces that need the oil the most are probably scored and damaged, ready to fail at any moment. Get this engine throughly checked out by another mechanic, including oil pressure tests, compression test, and leak-don test to spot any damage.

Thanks for the reply! I totally believe you, but do you know where this might be documented so I can show it the mechanic?

All I would need to do is cut open the oil filter and look for metal particulate in the filter media.

Tester

Very few cars have ever been built with a low oil pressure shutoff feature and your Honda is not one of them.

Yes, a badly damaged engine may appear to run fine when topped off with oil but it’s damaged goods and may give up at any time.

This mechanic is in CYA (cover your axx) mode and is feeding you a line of BS in the hopes that you will go away. He owes you a new engine whether he likes it or not; and he won’t like it you can rest assured of that.

Why do they even bother putting oil pressure gauges and warning lights in cars?? Nobody pays any attention to them…

New engine?? This is a 2002 Honda… How about a used engine with similar mileage…

I agree with you. Most just turn up the radio and revert to Karaoke mode to drown out the knocking rod bearings.

By new I meant new to the car if nothing else. Either way, the OP may be in for some additional BS and foot dragging.

No such mechanism. It would be stupid. Imagine your engine losing oil pressure as you were navigating a twisty mountain road and the engine quit, depriving you of power steering, power brakes, etc. You could die, all to save an engine.

Having said that, your engine may run ok now, but its life has been severely shortened, Cars are not like people, where what doesn’t kill you makes you stronger. What doesn’t kill the engine just brings the end a little closer.

A new engine is not in order, but a used one with similar or fewer miles.

No you don’t have auto shutdown. When the noises started the damage was significant. When the smoke comes out of the engine compartment the motor is severely overheated due to all the friction of raw metal grinding on raw metal. The bearings will be burned out, the pistons and rings have scored the cylinders and the head is likely warped from the heat. The motor can run like this when you put oil in it, but it won’t run well, it won’t have much power, and it won’t last long.

The only way the motor could survive is to turn it off as soon as the “oil” light came on. Once the noise started it is all downhill from there.

ALL cars have a mechanism that shuts down the engine if the oil pressure gets too low. It is called “seizing”. Unfortunately, it shuts the engine down permanently.

I’ll repeat it…Why do people continue to drive after the oil light comes on? The oil light means STOP NOW! Do not pass go, do not collect $200. Shut it down immediately!

OH…DUH, my fault…I didnt read your question properly…no no mfg co puts a shutdown in their cars or at least not many if there are any…With the way people are and how they treat their cars I think there should be tho.

I have done it before tho…

It is possible to wire up a relay to break your ignition circuit in the event of low oil pressure…In fact it is extremely easy…IF you know how to wire a relay and how to integrate it into the cars ignition harness.

I have done it on 3 vehicles I have had over the years just for giggles.

The only thing you need to know aside from all the relay wiring is that upon startup you would need a switch lockout system…when the car is not running and or being cranked…it doesnt have oil pressure…so you lock it out…start the car…turn the oil shutdown relay on…then you are protected…I am sure you could rig in an electronic device to do this for you but… The major problem with this is if you forget to switch your protection circuit back on…you are unprotected…and that will happen…

So to answer your question…yes its possible, but it is probably outside the scope of your abilities… and without some tyrpe of device to disable the system when there is low oil pressure as there is during startup…your system will have a very big weakness in its design. I could prob get around this using a diode…or an electronic box of some sort…again…if it is getting outside my level of experience…I am afraid it will be far out of range for most…

I had a 1998 Oldsmobile Intrigue which and both an oil pressure light and an oil level light. I don’t know which one did it (I suspect the oil level system) but it shut the engine in a fast sweeping turn when I was going way fast and plastered all the oil against the right side of the pan.

I will never knowingly buy a car with that system again.

My 1975 Civic had an electric fuel pump coupled to the oil pressure sensor with a relay.
This was there to keep the fuel pump from running when the engine wasn’t.
That could stop the engine if oil pressure were lost, but it would take awhile for the carburetor bowl to empty.

I think it would help on modern cars if the loud, annoying seat belt buzzer were triggered by the oil light.

You don’t need to show it to the mechanic. He already knows. He’s lying.

The mechanic is wrong on two counts.

First, you have no such mechanism. My '72 Vega had that, but it was because GM was testing aluminum engines with unlined cylinders and they needed to add extra protection. It didn’t work. The engines self-destructed anyway, even with oil. But that’s another story for another time.

Second, there was definitely damage. The damage could range from reduced engine life to severe internal damage manifesting itself as poor mileage, poor operation, and burning oil. Your cylinders are pretty much guaranteed to be scored.

And perhaps “bearing knock”, a condition wherein the damage to the bearings (I guarantee you have some) is severe enough that the crank and bearing surfaces are no longer consistant enough to maintain the proper pressuruzed oil film between the corresponding surfaces…and they bang against one another.

Monitor your oil usage very carefully. And look for smoke upon acceleration, upon deceleration, and upon startup. Have a friend follow you up the highway watching for smoke. Smoke under any of these circumstances is bad news. Sadly, the only way to definitively evaluate the engine would be to do a compression check and then open it up, to drop the oil pan and pull a few bearing caps. A compression check would be prudent, but may or may not be definitive. If it’s bad, it means damage was done, but of it’s good it doesn;t mean the bearings weren’t damaged.

A 72 Vega had ANY engine component made of Aluminum?..interesting…I have to look that up.