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by consp 1858 days ago
Well bad news for all gas powered car owners: performance and mileage will degrade over time. Maybe not by a software update (unless you own a specific diesel car) but they will definitely degrade and quite significantly as well.

Edit: do note this applies to older cars, it's a bit slower than EVs but 10year old cars will not have the same mileage and power as a new one even with the same specifications.
2 comments
Unklejoe 1858 days ago
> Well bad news for all gas powered car owners: performance and mileage will degrade over time. Maybe not by a software update (unless you own a specific diesel car) but they will definitely degrade and quite significantly as well.

This is not true, especially the part about "significantly".

The only real mechanism for a loss of performance over time would be if the engine's compression starts to drop as the rings get worn, but this isn't an issue on any modern engine.

Take a car with 10k miles and run it on a dyno. Dyno the same car again at 150k miles and it will probably be within 5%. In fact, performance may even go up as the motor "loosens" up.

This has been my experience.

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YarickR2 1858 days ago
Lime, actually ? Any data confirming that, and any explanation of such a behaviour, if true ? Like, one if my cars has around 300kw engine (400hp). How much I should lose in 10 years, if your claim is true ? And where are the losses ? I can't imagine anything besides loss of compression in cylinders, but that's tiny
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opwieurposiu 1858 days ago
Loss of compression comes from material breakdown, the other big one is from dirt build up. Dirt in the injectors causes bad spray pattern. Dirt in the cooling system reduces heat rejection. Dirt in the lube system increases friction losses. Dirt in the intake and exhaust causes pumping losses.

The amount of dirt a car is exposed to varies by 2-3 orders of magnitude between a farm truck compared to a sports car.

Rarely will you see an old sports car lose more than 20% power. Farm trucks lose 50%+, and the farmers keep running them until they just don't move at all.

*Side note, dirt does sometimes help. As a teen, I had an old ford festiva I shared with my brother. One day we washed the filthy engine bay and after that the thing would not idle. Turns out the dirty grease was plugging a vacuum leak around the pivot on the throttle valve.

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