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Extended idling of Infiniti Ex35 due to brain block

My wife forgot to turn-off the engine and the car idled for 12 hours before I discovered it. I plan to change the oil. What other maintenance issues are called for or problems “down the road”.

I think the car will be fine. The only issue would be if overheating occurred and coolant was lost but at this point I read this as not happening.

You’re going to have to put gas in it but outside of that should be no problems if it didn’t over heat. Lots of cars spend a long time idling like in traffic, patrol cars, taxis, and so on. They only thing is they usually have the heavy duty cooling system with larger radiators is all. Even if it did over heat, I’d be very surprised if the Infinity didn’t have an over heat prevention mode that would start to shut cylinders down to prevent damage. But I think if you didn’t find any coolant on the ground or other evidence, not a big deal.

Thank you Bing and ok4450-- Marine dad.

Out of curiosity, how exactly did this end up happening? I hope the car wasn’t in your garage at the time.

Your wife isn’t the first person who has left a motor running and she won’t be the last. A friend of mine did the same thing. He had owned a 1962 Ford Falcon and the engine in the Falcon had solid lifters and was noisy from the time it was new. He traded the car for a 1979 Mercury Montego. The Montego was so quiet in comparison to the Falcon, that he left it running for a whole day while he was at work. It was in the spring so the outdoor temperature wasn’t too hot. At any rate, there was no harm done.
The Stanley Steemer carpet cleaners that do our carpets have equipment that is run from the power take off on the van. That vehicle sits in the driveway for a couple of hours with the engine revving while the servicemen do their thing. In my previous house, I had insulation blown in the walls. The truck ran the blower for the insulation from the truck engine through a power take off and that engine ran for 8 hours in the driveway.
I’m sure your car is fine.

I would not worry much about it or think much of it.

Lion9car has a very good point about the car idling in the garage as that can be extremely dangerous.

About 10 years ago we had a very bad ice storm here in OK and were without electricity for almost a week, as was everyone within an 80 mile radius.
A high school friend of my oldest son was married out of high school and living in a neighboring town. Her husband was using a portable generator for power and parked it in the garage. His wife survived but unfortunately, he did not and passed away due to CO poisoning.

A portable generator running in a closed area may be worse than a modern automobile with a catalytic converter as far as carbon monoxide output is concerned.
In the building where I worked before I retired a year ago, a big emergency generator with a Caterpillar diesel engine was installed. Unfortunately, the air intake for the HVAC for the building is near the exhaust of the engine. When the engine is started, the entire 4 story building smells like diesel exhaust. The generator was purchased to keep computer equipment going through Y 2K. However, the installation didn’t take place until March of 2000, after Y 2K was no longer a problem. I questioned the administration of my university about the need for the generator and was informed that my building is now ready for Y3K.

A modern engine that’s operating properly can idle indefinitely without a problem…at least until the gas runs out. Engines no longer run rich, no longer operate with 165 degree T-stats, and no longer build up carbon during extended idling the way the old 1960s carburated engines did. As long as the luberication system keeps lubing, the cooling system keeps maintaining prpper operating temperature, the sensors keep driving the ECU to squirt the proper amount of fuel, and the oxygen sensors keep tweaking the mix, absolutely no damage will ensue.

Well, that is unless it gets stolen…

car was parked in a large open parking lot

The car is fine. And you, my friend, are very lucky.