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Why do heavy vehicles almost always use diesel engines?

Torque is the name of the game. High torque is needed to move heavy loads. If comparing a gasoline engine to a comparable diesel engine the diesel will always have higher torque. The higher torque ...
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29 votes

Small amount of wrong fuel type put in the tank

The main concern with using petrol in diesel systems is that diesel is used to lubricate the fuel pump, which petrol cannot perform adequately, which will shorten the useful life of the fuel system. ...
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27 votes

Why do heavy vehicles almost always use diesel engines?

A major, but often overlooked, reason for the dominance of gasoline engines in passenger vehicles is the need for diesel engines in heavy vehicles. A given quantity of crude oil, depending on its ...
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22 votes

Why do heavy vehicles almost always use diesel engines?

To OP’s main question: “Why do heavy vehicles almost always use diesel engines?” Answer: Cost and dependability. Diesel engines are significantly more expensive, but have lifetimes many times greater ...
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17 votes

Why not use gasoline on diesel engines or vice versa?

You "can" use diesel in a gasoline engine. In the sense that it will run, but it will run poorly and smoke A LOT. But the problem with gasoline in a diesel engine is that diesel engines rely on ...
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16 votes
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Why does diesel engine have redline much lower than petrol engine redline?

In Short its based on low burn rate of diesel plus the longer stroke of the diesel engine. First you must understand the difference between these engines, the diesel works on purely compression of ...
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16 votes
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Diesel Engine Runaway - What is it?

Since the diesel has no physical throttle, power is controlled by limiting fuel. Air is always available so any unintended, un-metered fuel will cause the engine to increase rpm and power output. The ...
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16 votes
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Small amount of wrong fuel type put in the tank

The main problems from misfueling a diesel car with petrol stem from the fact that (as Zaid points out) petrol doesn't provide the lubrication effect of diesel fuel and as a solvent it can actually ...
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13 votes
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Modern cars and diesel warm-up time

I have both a 2004 Bora TDI (Jetta Mk4 in the US) and a 2012 Mk6 TDI Golf. When either of these cars requires it's warm up system, it will automatically switch it on for the time it needs. This is ...
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13 votes

Why not use gasoline on diesel engines or vice versa?

I would say there are two major reasons. First, the seals and o-rings used in diesel engines can't tolerate the chemical composition of gasoline. They are designed to tolerate the chemical ...
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13 votes
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Why are VW recalling their cars to remove a defeat device?

The recall is not to remove the cheating logic; it is to actually make the engines meet emissions requirements so they do not violate the law any more. From Autoblog's initial article on the scandal: ...
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13 votes
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Two-Stroke Diesel Engine - Do they use forced induction on them?

The only two stroke diesel i'm aware of is the Detroit diesel. The Detroit diesel does use forced induction but not in the way that you think. From your description it sounds like your describing a ...
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13 votes
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Is it possible for a diesel engine computer to detect (and prevent) a runaway condition?

The common way that effective overspeed protection is provided on diesels in the oil and gas industry is way more simple than using electronics to effect a shut down. The only effective and reliable ...
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12 votes

Why does a diesel sound like that?

As already stated, the ignition source between gasoline/gas engines and diesel engines are different and this is the primary reason for the difference in sound. I will try to explain those differences ...
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12 votes

What's the cause of Diesels' typical clatter noise?

Two types of sounds There are two sound types that emerge from a diesel engine. Combustion Noise Mechanical Noise Combustion noise is created by the compression ignition process which compresses ...
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12 votes
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How did they start diesel engines before the glow plug was invented?

Glow plug is merely an aid for starting the engine. There are many designs still produced today without any glow plugs (eg military diesels run without any electricity), and even many modern diesel ...
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12 votes

ATF in engine oops

I would run the engine again for a few minutes and then drain that engine oil as it will have any ATF that was still in the galleries. Then fit a new filter and refill with fresh oil. After that you ...
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11 votes

Why do heavy vehicles almost always use diesel engines?

Given two engines of similar weight, both operated at their respective optimum efficiency (i.e. maximum mechanical work done per unit of chemical enthalpy in the burnt fuel), you will end up with ...
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11 votes
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How are diesel engines better for the environment than gasoline?

They aren't better for the environment But efficiency is often confused with emissions. The average person would think that because diesel engines are more efficient and burn less fuel, they must be ...
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11 votes

Small amount of wrong fuel type put in the tank

This will not be a problem - in fact, some of the older truckers used to add 2% of petrol to the diesel to help in winter conditions to help reduce waxing of the diesel fuel.
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10 votes

Why does a petrol engine need to maintain an air-fuel ratio, while a diesel engine doesn't?

It sounds like you already know why a gasoline engine keeps the fuel/air ratio as close to the stoichiometric ratio as possible, but just for the sake of information for anyone else: The ...
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10 votes
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Why don't all diesel engines have throttle plates?

tl dr: By adding a throttle plate, it creates the vacuum needed to draw in gasses from an EGR valve. Since diesel engines are designed to run lean, they don't need throttle plates to run. They ...
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10 votes
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What would cause a short to ground while driving - how to locate the problem?

The most likely cause is that the cable that runs down to the starter motor has been rubbing against the body or the engine and has worn through the insulation.
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9 votes

Why not use gasoline on diesel engines or vice versa?

You can see the ill-effects of misfueling in this episode by Fifth Gear. They put petrol (gasoline) in a diesel car and vice versa. A summary of the differences between the two fuels: Diesel does ...
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9 votes
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Why not use gasoline on diesel engines or vice versa?

You can run gasoline in a diesel motor, but it causes problems. As mentioned elsewhere, when you compress the fuel/air mixture enough, it gets really hot then ignites. With diesel, this is ok, because ...
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9 votes
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What's the cause of Diesels' typical clatter noise?

The engine operates on high compression to ignite the fuel at very low RPMs which gives it it's distinctive sound. The lower RPM makes the ignition of each cylinder easier to hear and the compression ...
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9 votes
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Diesel engine timing?

Diesel engine timing is accomplished through the fuel injectors (they inject fuel at the proper times). Proper timing prevents pre-ignition because there's no fuel in the cylinder yet to ignite. Glow ...
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8 votes
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Would a non-turbo diesel perform better in high altitudes than a comparable gasoline engine?

Non-turbo diesels lose less power in the Rockies At least according to the SAE J1349 standard. (Calculations shown below). Assumptions Dry air pressure in the Rockies = 90 kPa ( at 3000 ft) ...
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8 votes

2004 powerstroke white smoke now no start

I'm not a diesel mechanic but after a quick search the number one cause of no starts on the 6.0 is lack of oil pressure. The injectors need 500psi minimum to operate. This indicates there is not ...
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8 votes

Does free revving a diesel engine to 4000 rpm (1.6 crdi- hyundai) cause any damage?

Short answer - no. It's perfectly okay. And , it's also perfectly okay to be annoyed. It's one of those things mechanics like to do (no offence to anyone). Similar to endlessly hitting refresh on a ...
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