IMHO a no no! The temperature gauge may get up to temperature but the oil temperature won’t., resulting in condensation in the engine.
Completely agree!
I agree with that, but I wonder how much harm it does really. Lots of people by me do what I’d never do- start their car up, reverse it off the drive and turn it off a minute later, when its parked outside their house on the road, so they can potter about doing on jobs all day on a car free drive, and to then do the opposite and put it back on later on in the day. To the best of my knowledge they have them serviced often, so changing the oil etc, so I wonder, really, if it does any harm; their cars seem totally fine!
The temperature gauge will not get up to temperature if the engine is not warmed up. I have worked on cars all my life where do you get this information from?
My understanding is that the temperature gauge shows the temperature of the cooling system, not the oil temperature which is more important. To illustrate, a liquid cooled motorcycle may show that the engine is up to working temperature but if you put your hand on the crankcase (the equivalent of a sump on a car) it may only be warm rather than hot.
In addition, if the engine remains at tick over or even a fast tick over, say 1500 rpm rather than a normal driving load which may be at 3 or 4000rpm, the oil is unlikely to reach its correct operating temperature.
Interesting. I would point out however, that a stored vehicle in a garage is unlikely to reach 120 kph*
*unless it is on a rolling road
Most engine wear occurs at start up until the oil is up to temperature. Fact.
So how is the condensation getting in the engine?
Water vapour is produced as part of the combustion process hence the vapour that appears from the exhaust when an engine is first started on a cold winter morning. Some of that water vapour will find its way into the sump. Admittedly less of a problem in modern engines because the amount of coolant circulating is much less than in older engines so warms up more quickly. A car that is frequently used for short journeys may have “mayonnaise” around the oil filler cap as the water vapour emulsifies with the oil but doesn’t evaporate because the oil doesn’t get hot enough.
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I used to see this on older cars back in the 70s and 80s, but I have not seen it in modern engines at all.
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No one is saying it isn’t fact, but the question is, really, what harm does it do in the grand scheme of things if someone started up their car now and again, let it idle, and turned it off. Like I said, the neighbours do it all the time and their cars seem totally fine. My up! gti, for eg, (touch wood) purrs like a cat, but I got it in 45K miles. Did the previous owner do 0.5mile shop trips as he was too lazy to walk? Who knows.
I think a lot is, again, internet car enthusiast hysteria. Like the good old 5 year old tyres question which often sees the sky falling in, yes it’s not ideal, but whether it really does any massive wrong is probably over reaction.
They cleaned up fine, but then it was not a dog when it was stopped being used either. The discs, pads, tyres were all just a few days old before it stopped being used.
That is an interesting comment about 5 year old tyres. I did a roadtrip this June to Italy and black around 2000 miles. The the car was fully serviced by the dealership before I left as it I do about 1500 miles every year (2009 2L NC) and have owned the car for around 3 years (garage stored). The tyres were easy 5 years old as the previous owner again only used the car in the summer. I drove the car down a German Autobahn at 120 to 145 miles an hour for an hour. The tryes still work perfectly today.
That’s got to be up to 145 klm, you must have one special MX-5 otherwise😁
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No thats 145 mph on the speedometer. Don’t forget Speedometers are set by the manufacturer to by 10% fast 100 mph is actually 90 mph.
I am not so sure you are correct anymore, particularly with japanese cars, apart from my MX-5 I have two Honda CRV and they at least are not running at speedo max minus 10%, try arguing the toss with the speed camera and even with a backup satnav, beware 
Yep my c320 merc and my Audi q2 run exactly what it says on speedo and GPS unit , they are auto…maybe this differs to manual car readings ?
I’m afraid its in legislation. Google it or set up a satnav Garmin and and check. I also have an old speed camera detector Road Angel its easy to see. When I was in Germany my Garmin was set to Kph so I didn’t speed. Germany doesn’t have speed cameras and I can only believe they respect the law. However on sections of the Autobahn you can go as fast as you like. I was chasing a Ferrari when my Speedo reading was 145 mph……the Ferrari won the race.
Is the GPS unit separate from the the car? If not try a separate Garmin and compare. All vehicles are are set to 10% faster than the actual speed limit 55 mph is actually 50. If you don’t believe me Google it. I had Audi company cars for many years and a Road Angel the Road Angel always gave the real speed.