Any car mechanics here?

[Sebring Studios]

Here's what happened:

Driving my full-size Dodge van down the freeway today. (Vegas - Heavy traffic - 110 in the shade)

Radiator temp guage shows hot but not in the danger zone. Oil pressure guage is fine. Turn off AC to cool down engine. A few minutes later truck loses power. Barely make it to the shoulder. Oil pressure guage now showing zero pressure/red light on. Stop engine immediately. No smoke or odors of burning anything.

Call AAA, they tow back to my house - Let it cool for a few hours and tryed it. Starts like a new car. Test drove it, drives great as always. So I'm wondering...

Could it be that either the engine oil, transmission fluid or engine coolant overheated to the poitn where the system shut down? Are there safety thermostats in auto engines that shut the car down to keep it from burning up?

Something must have overheated, doesn't seem to be any permanant damage. All fluid levels are fine.

Any ideas what happened? Thanks in advance for opinions.

[Semi-Retired-Dave]

Might be your Oil Pump, If you said this..."Oil pressure gauge now showing zero pressure/red light on. Stop engine" that is serious. I wouldn't chance it. Depending on what year the Van is, but it should be easy to drop the pan and replace the Pump.

But I would double check with a Mechanic first.

Ugh, shouldn't have started it back up if the oil pressure went down, could have been a bad oil pump, in which case your engine would be ruined.

[Helix]

Sounds like the ignition module got too hot and shut down until it cooled off.
I am not familiar with the Dodge vans, but what you described was the identical symptoms that effected the Ford Rangers that had the ignition module on the distributor a few years back. The would get too hot and the engine would shutoff. It was like you turned the key to the off position, and wouldn't restart until it had cooled down.
You could pour bottled water on the module to cool it and restart.

[Sebring Studios]

Originally Posted by Helix

Sounds like the ignition module got too hot and shut down until it cooled off.
I am not familiar with the Dodge vans, but what you described was the identical symptoms that effected the Ford Rangers that had the ignition module on the distributor a few years back. The would get too hot and the engine would shutoff. It was like you turned the key to the off position, and wouldn't restart until it had cooled down.
You could pour bottled water on the module to cool it and restart.

I think that's the answer. Runs like it's right off the showroom floor tonight. I'm keeping a close eye on it and just driving locally for few days. Oil pressure/levels are fine, everything's back to normal. (I hope). I was driving it all day in heavy freeway traffic on the hottest day of the year.

Reminds me of when I had a '69 Camaro. The starter motor was next to the exhaust and wouldn't start when hot. Chevy actually came out with a 'fix' for it, a half-assed heat shield that never worked. I just always kept a couple of gallons of water in the trunk to pour and cool. Worked every time.

[Jon Oso]

It just sounds like your ECU or whatever is driving your engines brain overheated and had a safety-off switch so it didn't melt the computers internals.

I would flush the radiator fluid, trans fluid and oil just to be safe and have them inspect the oil and trans fluid when it's being drained to look for any metal flakes or anything like that. You could have severely damaged your motor but lucky for you it wouldn't turn on.

[JimmiDean]

I was on the floor as a tech for over 20 years and owned my own shop so take it for what ever you feels it is worth.
You more most likely do not have an oil psi problem or module problem.
You have what you first noticed and over heating problem, once the engine gets hot enough the engine oil will lose its viscosity and thin out to the point you will have little to no oil pressure.
Fuel will begin to vapourize in the fuel rail and the engine will stop.
Once cool it would seem to be fine however it will return.
I have no idea why you overheated but this type of problem will not go away on its own and a some point the motor will be damaged.
Those vans are famous for tossing head gaskets but it could be as simple as a fan relay, thermostat,needed flush, water pump and on and on.
you could also have an A.C problem if the secondary fan is not cooling the condensor when operated.
Long and short take it in before you need a motor.
Cheers

[JimmiDean]

Originally Posted by Sebring Studios

Here's what happened:

Are there safety thermostats in auto engines that shut the car down to keep it from burning up?

Any ideas what happened? Thanks in advance for opinions.

Short answer NO if you push it it will run until something fails

[rowan]

Originally Posted by JimmiDean

You have what you first noticed and over heating problem, once the engine gets hot enough the engine oil will lose its viscosity and thin out to the point you will have little to no oil pressure.

I've had an oil pressure alarm a couple of times when idling at a red light on a very hot day. Putting the trans into neutral and pushing the accel slightly clears the alarm almost immediately. (This was just a reflex to try to get the oil circulating, and it happened to work)

If it's happening frequently then obviously there's a more serious issue, of course...

[rowan]

Originally Posted by JimmiDean

Short answer NO if you push it it will run until something fails

My car engine has some sort of feature where it can run without any coolant at all, it progressively shuts down cylinders to keep the temp down. Sounds kinda "cool" but I'm not sure I'd want to test that capability anytime soon. The transmission also has a "limp home" mode which locks it into third (1:1 ratio) when there is a fault, including overheating.

[gornyhuy]

I think your gas tank is low on sugar.

[BV]

Originally Posted by Sebring Studios

Here's what happened:

Driving my full-size Dodge van down the freeway today. (Vegas - Heavy traffic - 110 in the shade)

Radiator temp guage shows hot but not in the danger zone. Oil pressure guage is fine. Turn off AC to cool down engine. A few minutes later truck loses power. Barely make it to the shoulder. Oil pressure guage now showing zero pressure/red light on. Stop engine immediately. No smoke or odors of burning anything.

Call AAA, they tow back to my house - Let it cool for a few hours and tried it. Starts like a new car. Test drove it, drives great as always. So I'm wondering...

Could it be that either the engine oil, transmission fluid or engine coolant overheated to the poitn where the system shut down? Are there safety thermostats in auto engines that shut the car down to keep it from burning up?

Something must have overheated, doesn't seem to be any permanant damage. All fluid levels are fine.

Any ideas what happened? Thanks in advance for opinions.

Once the engine stalls there is no oil pressure if it's an automatic transmission, so naturally the oil gauge will show 0 if your engine stalled.

What year van is it? Is it carbureted or fuel injected?

As explained above the elec ignition module can get hot and shut off the engine, then work again when cooled. Quite common with Fords in the late 70's and early 80's. You can test it by cooling it with a water hose if you can duplicate the problem again.

Another intermittent problem could be a fuel line vapor lock. This usually happens with hot temps, and or if the gas cap or tank is not venting properly.

If you blew a head gasket more than likely you will have water in the oil as well as white smoke coming out the tailpipe. white smoke = water, blue smoke = oil, black smoke = fuel