Oil pressure light in late model cars?

[Boomyal]

If you experience low oil pressure, in this case, due to insufficient oil, does the computer automatically kill the motor? A neighbor lady just blew out all of her oil due to a loose and improper oil filter. She reports that just about as quick as she saw the light, the motor shut off. It is in the shop now and after an oil refill and new filter, the motor, preliminarily seems to be OK. This would certainly be the case if there had been an automatic shutdown. If heat and friction caused it to stall out, there would likely be damage. This is on a 2001 Chrysler (dodge) V6.

 

[bigdee]

IDK for sure but I don't think so. I have a Grand Cherokee (another Chrysler product) that actually has low oil pressure and light constantly comes on at idle....been that way for +60k miles. It most likely stalled when she let it idle because the lifters were collapsed from lack of oil.

 

[Gyrene]

I'm on s PT Cruiser car forum - made from 2001 - 2010, and people frequently report oil "idiot light" comes on - usually due to a faulty sensor, and car runs fine.

 

[Boomyal]

I'm on s PT Cruiser car forum - made from 2001 - 2010, and people frequently report oil "idiot light" comes on - usually due to a faulty sensor, and car runs fine.

In this case it worked fine. A garage did an oil change, used the wrong filter and did not tighten it. There was no measurable oil on the dipstick after the motor shut down. It was all on the front brakes and the underside of the car.

 

[Gyrene]

In this case it worked fine. A garage did an oil change, used the wrong filter and did not tighten it. There was no measurable oil on the dipstick after the motor shut down. It was all on the front brakes and the underside of the car.

I get that -- but my point is low oil pressure sensor doesn't shut off engine - at least on PT Cruisers.

 

[sam am I]

My folks owned a new from the dealer Fiat that did...........With pressure, the oil pressure sender/switch would close and was wired in series with the fuel pump's relay coil.........Found this out the hard way, the oil sender wire fell off one day on the interstate, shut the fuel off and she rolled to a dead stop.

 

[bigdee]

She reports that just about as quick as she saw the light, the motor shut off.

Loss of oil to hydraulic lifters probably caused some of them to collapse which would cause engine to stall when she let engine idle.

 

[MTboatguy]

I have never run into an American car that has an auto shutoff feature. We have customized our off road trucks to shut off with low oil pressure.

 

[spoilsofwar]

I could see a certain degree of liability with such a feature; you're heading down a busy multi-lane highway and you lose oil pressure, engine shuts off, you lose power steering and then your mind, and end up slamming into a bus full of orphans.

Or, you're headed down a winding mountain pass, same thing, now you smash through the guard rail and plunge down a cliff killing you and your passengers in a fiery crash.

Save the engine, kill the occupants? Seems like a good enough reason this feature doesn't exist to any real extent.

 

[oldjeep]

Depends, some cars will go into limp mode if the oil pressure stays low too long. I know that the MPI 5.7L in my boat does.

 

[Boomyal]

I could see a certain degree of liability with such a feature; you're heading down a busy multi-lane highway and you lose oil pressure, engine shuts off, you lose power steering and then your mind, and end up slamming into a bus full of orphans.

Or, you're headed down a winding mountain pass, same thing, now you smash through the guard rail and plunge down a cliff killing you and your passengers in a fiery crash.

Save the engine, kill the occupants? Seems like a good enough reason this feature doesn't exist to any real extent.

all good points sow. Indeed except for the cataclysmic ends, that is exactly what happened to this lady. She was in the middle lane of a three lane freeway when th engine shut down. She had to wrestle the car over to the side of the fwy and straight leg the brake pedal to stop it. If it shut down due to heat and friction, then she has some damage problems that have not, at this moment, shown themselves.

 

[thumpar]

I am with SOW. When the engine dies you lose brakes and power steering. Seems like a liability if the engine just died. None of the vehicles that I have owned would kill the engine with low oil pressure.

 

[WIMUSKY]

I've never heard of an auto shutoff. Makes no sense for the same reasons given above. Haven't heard of a limp mode either, except in boats. My OB has limp mode. Don't have to worry about getting run over on the lake... Hopefully she hasn't done any internal damage.....

 

[MTboatguy]

I have owned cars with limp mode in them, my Grand Cherokee went into limp mode when the O2 sensor went bad.

 

[MTboatguy]

I am with SOW. When the engine dies you lose brakes and power steering. Seems like a liability if the engine just died. None of the vehicles that I have owned would kill the engine with low oil pressure.

Heck, I learned how to drive without power steering, power brakes and manual trans!

 

[spoilsofwar]

Yeah, I had a Nissan 350z that had a limp mode, activated once when it was overheating due to a coolant leak.

 

[thumpar]

Heck, I learned how to drive without power steering, power brakes and manual trans!

Me too but most people don't. Also when you have the power features it doesn't work the same as if it was originally manual. When the engine stops on a car with power steering and power brakes it is VERY hard to steer or stop. If an engine just died I don't think most people would be able to handle it.

 

[MTboatguy]

Me too but most people don't. Also when you have the power features it doesn't work the same as if it was originally manual. When the engine stops on a car with power steering and power brakes it is VERY hard to steer or stop. If an engine just died I don't think most people would be able to handle it.

You want something fun to handle, we were on the way home from camping a couple of weeks ago and the darn power steering pump went out on the motorhome, talk about fun, over 10,000 pounds and no power steering!

 

[gm280]

MT, usually with power steering and brakes, there are different gearing ratios that make it a ton harder to stop and steer then no power steering or brakes. It isn't just adding extra capabilities with the power booster and pump for the steering. The gearing or ratios are totally different. I bet you did had a really fun time controlling that motorhome though.

As for the oil pressure shutting down an engine if the pressure drops out, I 've never seen any such thing myself. But I did have an inline 6 cylinder that had a oil pressure switch that you had to crank the engine for a few turns to build oil pressure before the ignition would fire up.

 

[MTboatguy]

GM, it was indeed fun, it went out on a sweeping curve and if that guard rail had not been there, you would be posting condolences!

All it ended up costing me was a lower awing arm but my wife sure didn't let me forget it! She still gives me the evil eye when I start laughing about it!

:lol: