Laser Ignition May Replace the Spark Plug 388
dusty writes "Laser Focus World has a story on researchers from Ford, GSI, and The University of Liverpool and their success in using near-infrared lasers instead of spark plugs in automobile engines. The laser pulses are delivered to the combustion chamber one of two ways. One, the laser energy is transmitted through free space and into an optical plug. Two, the other more challenging method uses fiber optics. Attempts so far to put the second method into play have met some challenges. The researchers are confident that the fiber-optic laser cables' technical challenges (such as a 20% parasitic loss, and vibration issues) will soon be overcome. Both delivery schemes drastically reduce harmful emissions and increase performance over the use of spark plugs. So the spark plug could soon join the fax machine in the pantheon of antiquated technologies that will never completely disappear. The news release from The University of Liverpool has pictures of the freakin' internal combustion lasers."
Flashing lights (Score:5, Funny)
I'd be too afraid... (Score:2, Funny)
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Re:Flashing lights (Score:4, Funny)
I've seen those installed. Be assured - An adult driving a car with a red swooshing light thing does not look nearly as cool as we all remember KITT and Michael to be.
Re:Flashing lights (Score:5, Funny)
David Hasselhoff [youtube.com] doesn't look nearly as cool as we remember him to be either...
Re:Flashing lights (Score:5, Funny)
Nope, he still does ... :
http://video.google.com/videoplay?docid=-3382491587979249836 [google.com]
Comment removed (Score:5, Funny)
Re:Flashing lights (Score:4, Informative)
Seems like a good way to get a ticket for impersonating an emergency vehicle.
Indeed. Though it depends on your state, there are restrictions on what lights you can put on a car and in what colors. Many restrict red lights to the back of the car, and some don't allow any light colors than red, white, and yellow on the back of a car (e.g. no neon purple illuminated plate frames). I heard a story from a police officer who pulled someone over just as he left the dealer's lot for having too many high deer lights on his brand new truck; the guy was pissed they'd sold him a car in an illegal configuration.
And just because something is legal in the state in which your car is licensed doesn't mean you won't get ticketed when you cross into another state. Permanent window tinting is another per-state restriction; you may have to drive with your windows open to stay legal, which will suck in states that experience Winter.
Re:Flashing lights (Score:5, Funny)
Re:Flashing lights (Score:5, Funny)
Wait wait wait, two things
1. You're saying Members Only jackets are out of style and have been so since the 80s?
2. Who are you calling a jackass?
So what happens (Score:5, Interesting)
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I'd be pretty impressed if they can make high energy fibre optics work for any length of time in a consumer auto. Cleaning and mating optical connectors can be annoying in the clean, vibration free, and relatively low power confines of data transmission. Anything connected to an engine, designed to be worked on by mechanics, and carrying enough power to set things on fire is going to be interesting.(though probably a great resource for tinkerers w
Re:So what happens (Score:5, Insightful)
We're not talking gigahertz, 0.00001% error rate stuff. We're talking honking big pipe firing a few hundred times a second.
My first thought was, 20% loss? Who cares!??? Just stick a bigger laser on the other end!
Seriously, this is one of those things where power is good, and more power is better. Early ignition was pretty pitiful. Now electronic ignition is pretty much bullet proof.
I expect this to be like fuel injection, going from expensive trouble prone disaster to rock reliable. Once they figure it out, it'l be like injectors - maybe 200,000 mile service.
Honestly, I can't wait. I expect reciprocating engines will be with us a long, long time, burning some sort of liquid fuel.
Re:So what happens (Score:5, Interesting)
I don't doubt that they'll work it out in the end, engineers have a long history of being clever like that; but it is going to take a giant pile of tweaks on top of the naive implementation.
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I remember in the early days when they went to electronic ignition the spark plug wires couldn't take it either and would fail quickly - they'd get brittle, crack, and lose the ability to conduct. After a while, spark plug wires got better; I don't know anyone who actually replaces them unless it's a high-mileage vehicle (like my 1989 Trooper, about due for another set at 224K miles....)
As you say, the engineers will work this out, but not before some pain....
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Is that so? I've never had a fiber GBIC go bad on me and my rig is a traveling rig with over 60 switches and at least as many GBICs. We role in the dust and our biggest problem is patch cables which you sometimes have to rub on your shirt to clean up. GBICs themselves can be blown out with compressed air, not the canned kind of course.
Given that HP has a lifetime warranty on them I wonder if anyone else has had that experience? I don't think solid state lasers are nearly as unreliable as you claim but I'll
Re:So what happens (Score:5, Funny)
You ever had a car with Lucas electrics?
Two. One for the road and one for the mechanic.
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Diesels don't use spark plugs, and already burn all the fuel in the chamber. They run inherently lean, which is why they produce no appreciable carbon monoxide. If you're seeing black sooty exhaust smoke from a diesel, either the fuel rack is turned up too far and it's dumping *way* more diesel in than you can burn, or the air filter is clogged.
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No, sorry that's crap.
Black smoke is due to mechanical failure, either rings allowing sump oil to burn or some other vector allowing oil into the chamber. Too much fuel gives a blue or white smoke. If you get a turbo blow, you get blue smoke out the back, wrong fuel-air ratio. Black smoke is caused by soot. If you have too m
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Wow, someone needs a reality check. Diesel in most places is comparable to gasoline and has a higher energy density than gasoline. Add in the extra fuel efficiency and the cost in cents per mile for diesel whips the pants off gasoline. The smoke you refer to was from high sulfur diesel which is no longer sold in the United States. Diesel has been shown to release less emissions than gasoline, and in fact VW is trying to reverse myths that you have with ad campaigns like this http://tdi.vw.com/a-coffee-f [vw.com]
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Partly, but it was mostly from the low-tech engines used (large mechanical tolerances, no turbocharger, indirect injection, etc.). My 1998 VW New Beetle TDI, which was manufactured well before the switch to ULSD, also produced* very little to no smoke because it has a comparatively modern and high-tech engine. It's not as high-tech as a 2009 TDI engine because it's two generations behind in fuel injection technol
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I'd be pretty impressed if they can make high energy fibre optics work for any length of time in a consumer auto.
My money is on the 'free air' optics. In reality, the optical paths and components could be enclosed in some sort of housing. This has been done for spark ignition in a few cars already. The ignition system is one module that sits on top of the spark plugs. In the optical equivalent, the lasers, mirrors and distributor function would be contained in an 'ignition rail', eliminating fiber optic losses and alignment issues.
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Re:So what happens (Score:4, Interesting)
Exactly.
What is the point?
Obscure claims of increased fuel efficiency and reduced emissions, based on what? A spark is a better combustion source than a laser.
This looks like a solution in search of a problem if you ask me.
Re:So what happens (Score:5, Insightful)
The laser can be focused to a specific point more easily, allowing it to ignite a stratified charge better. This makes it better at igniting a leaner mixture. Coupled with Direct Injection and maybe some octane boost trickery, this could make gas engines get the same compression ratio as a diesel while still reving over 3k.
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Re:So what happens (Score:5, Interesting)
When it comes to ignition, compression is never a problem these days. What compression does do is increase *heat*. So unless your running gasoline with a higher octane rating, you will get detonation and pre-ignition the higher your compression ration is. ....and what happens when you use a laser to ignite a large portion of the fuel/air mixture at once, rather than using a spark plug to ignite a small flame kernel and waiting for it to propagate? The fuel mixture burns much more rapidly, allowing you to run less ignition advance. The result is more power, fewer emissions, and the engine is LESS prone to detonation. So then you can jack up the compression ratio and gain even more power.
Re:So what happens (Score:5, Insightful)
You may be right, in that a spark makes a better ignition source. But, do we KNOW that, or do we just assume so? I won't argue the point, but I will point to explosives, and note that a spark is often not the best source of ignition. Naval guns use electricity to detonate primers. C4 and other explosives use a carefully controlled combination of pressure and temperature. In fact, those explosives can be set alight, and used to cook dinner, because the spark isn't what detonates them.
Gasoline? Internal combustion engines? They are terribly wasteful of both fuel, and energy. Even a very efficient gas burning engine pumps fuel out the tail pipe, which is the reason catalytic converters are required on vehicles in the US. If a laser can set off a more thorough, more efficient ignition, that burns ALL of the gasoline in the cylinder, fuel mileage will increase, for certain. Polluting emissions will probably be reduced. Is it worth the cost? Only time will tell.
And, THAT is the reason for research. Very few people will purchase these things if they add $10,000 to the cost of a vehicle - but if the cost is brought down to $50 per cylinder, they never have to be replaced, AND they increase fuel mileage even a little bit, people will buy them.
Let them research. If/when they have a product ready for market, I'll probably test it.
Re:So what happens (Score:4, Interesting)
Gasoline? Internal combustion engines? They are terribly wasteful of both fuel, and energy. Even a very efficient gas burning engine pumps fuel out the tail pipe, which is the reason catalytic converters are required on vehicles in the US. If a laser can set off a more thorough, more efficient ignition, that burns ALL of the gasoline in the cylinder, fuel mileage will increase, for certain.
Modern gasoline engines already burn something like 95%+ of the fuel that is pumped in so there really isn't that much room for improvement. I suppose any improvement is better than none at all but don't expect any miracles. FWIW this is one of the reasons those gasoline additives that claim to improve efficiency are mostly BS, even if they did cause the fuel to burn 100% it would be hard to even measure the difference in mpg.
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I realize it's a fad to crap on internal combustion engines. The fact is that they're by far the best thing we've got for the applications they're used in. If they weren't we wouldn't be driving gasoline or diesel powered cars right now. They provide the best mix of range,
Self Cleaning (Score:3, Interesting)
I would think it would be self cleaning, wouldn't the laser keep all the crap burned off of the lens ?
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Carbon don't burn too easy boss.
In most likeliness (Score:4, Interesting)
Don't think fax machine, think FD Trinitron.
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I would imagine that such a technology could be adapted to other fuel sources like hydrogen. In fact, I suspect that hydrogen engines might actually benefit greatly from this.
Re:In most likeliness (Score:5, Insightful)
I would imagine that such a technology could be adapted to other fuel sources like hydrogen. In fact, I suspect that hydrogen engines might actually benefit greatly from this.
I'm not so sure of that. Granted, you can use hydrogen fuel in an IC engine, but storing it is a big PITA. At sea level pressure, gaseous hydrogen has abysmal energy density per volume, and any solution for reducing that volume would have to be adapted for every car on the road. Meaning liquid hydrogen is a non-starter, pressurized hydrogen needs to be stored in a collision-rated tank, and hydrogen dissolved in or bonded with something else needs a cost-effective carrier of limited weight per fuel (else the energy density per weight or price per tank becomes a problem).
If we've got the hydrogen storage problem licked, and with all the R&D focusing on precisely that we very well might someday in the not too far future, then why use an IC engine over a fuel cell? In a FC + electric motor configuration, the engine makes very little noise, there are fewer moving parts than an IC engine, no need for a separate (and heavy) alternator + battery to power the electronics, and probably other advantages I've overlooked. The one downside is cost, which can probably be substantially reduced via mass production - the cost per cell is high now, but we aren't making them for every car on the road.
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If we've got the hydrogen storage problem licked, and with all the R&D focusing on precisely that we very well might someday in the not too far future, then why use an IC engine over a fuel cell?
Because fuel cells require high purity fuel, expensive materials, and are generally very delicate. An internal combustion engine is very durable, a known quantity, and quite cheap. Of course that may change when/if we figure out how to store hydrogen with an energy density similar to gasoline or diesel fuel but I'm not terribly optimistic on that.
But then your premise is that we don't have the hydrogen storage problem licked already. All we have to do to store that hydrogen in a form that is liquid at se
Re:In most likeliness (Score:5, Funny)
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Pure hydrogen has a terrible octane rating and is extremely inefficient in an IC. However, you can mix a little into regular gas to boost its octane rating, letting you run higher compression or turbo boost. It also increases the flame front speed, which is particularly good for Wankels. Mazda's Furai concept is being developed along these lines.
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It may be pedantic, but straight hydrogen should be thought of more as an energy store than a fuel source, i.e., as a gas or liquid battery. The energy used to create any amount of hydrogen is going to be higher than the energy returned in use, similar to how a battery requires more energy to charge than it will give back as usable electricity.
The advantage fossil fuels have is that the initial energy storage too
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"Hydrogen engine" is vague to the point of uselessness. It's like saying "Combustion engine", which covers everything from steam locomotives to rockets.
I suspect you read "hydrogen engine" to mean a fuel cell powering an electric motor. From the context, it sounds more like he meant an internal combustion engine, fuelled by hydrogen, which is a different beast entirely. Hence the confusion. An ignition source is indeed potentially useful for such an engine, though not absolutely necessary (not all IC en
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You'll still get carbon dioxide in the 'exhaust', though not carbon monoxide or those nitrous compounds you get from an internal combustion engine's exhaust. You won't need a catalytic converter, at least.
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Carbon monoxide is a product of all combustion, not just car engines.
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How pray tell does hydrogen and oxygen burning produce C02? It would be a bloody miracle if it did.....
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Nor is either compound produced by burning hydrogen. For that matter, you get no CO, nor CO2 from burning aluminum or magnesium powder, or any number of other flammable materials.
I think you meant "carbon monoxide is a product of any form of incomplete carbon combustion" in your original post. Not all combustion needs to involve carbon.
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Yes, my car only takes 2 shovel fulls of coal to make it o work and back.
Getting it started is a pain if I have forgotten my lighter fluid and I always have to park next to a water hydrant so I can re-fill the water tank....
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2. Get one of these fancy lasers to ignite it from a battery
3. Use a recirculating condensing water system
4. ???
5. Profit!
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Yes, my car only takes 2 shovel fulls of coal to make it o work and back.
What's that in rods per hogshead?
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..without the complexities of the internal combustion engine
What complexities are these? ICEs can be made with 2 moving parts.
Rockets can be made with zero moving parts. And there are very, very simple rockets in existence, dating back millennia (think fireworks). That does not mean "rocket science" is easy, and nor does it mean that the statement "rockets are complex" is in any way wrong.
Same goes for piston engines. Yes they can be "simple" - they made the first of the damn things in the days when people still though of "aether" and "phlogiston", it doesn't require advanced chemistry or physics. That does not mean they alway
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Another example of an improvement arriving to a technology just as it was obsoleted is the gas mantle, which improved the efficiency of gas lamps just about the time the electric light bulb came along.
PETA (Score:5, Funny)
Yeah, they're gonna be pissed.
Re:PETA (Score:5, Funny)
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IC engine (Score:4, Insightful)
inefficient. Adding a laser is not going to do much.
Re:IC engine (Score:4, Insightful)
But it's potentially enough. ISTM part of the reason the ICE has lasted so long is the continued incremental improvements that make it just good enough to stick with. Continued incremental improvements in fuel economy, at a rate roughly equivalent to the inverse of the rise in fuel prices will keep the modern gasoline powered ICE a viable alternative for a long time.
This kind of improvement, along with better optimized hybrids and other "transitional" technologies effectively allow us to maintain the status quo.
IMVHO, only two things will pitch ICE's off the top of the pile: 1) a radical, cheap, viable, ready-to-go, drop-in-now replacement, or 2) time, a long time.
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This kind of improvement, along with better optimized hybrids and other "transitional" technologies effectively allow us to maintain the status quo.
And we want that...why?
I'm personally in favor of a gas tax that increments $0.50/gallon every 18 months or so.
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Oh, I don't want that. Just stating what I think will happen...
Personally, I'm in favor of everyone (from consumer to corporation) getting their collective heads out of their collective asses and making real change instead of paying it lip service. But I don't see any flying pigs yet. And when I do, I'm sure they'll be powered by fossil fuel ICE's.
Spark up! (Score:2)
Man, you can use them to light cigarettes too! Oh hell... the fuel injector fire at the same time!
Great... (Score:5, Insightful)
Great, the laser pulses will probably be DRM encoded so that only authorized chips are used and vendors that insert the appropriate smart card can perform service on them...
The advent of CPU-enhanced cars is a great one, but this is one place where the govt really needs to step in an open things up. For standard engine codes, things aren't too bad; but Lord help you if you want to read an ABS or airbag code from a GM vehicle (for example). They're locked down. I have some decent PC-based code reader hardware and software, but in order to read the ABS error that my two vehicles are both showing (GM, learn to design ABS, will ya!), I need to spend hundreds or thousands on their own software/hardware to simply find out which of my four ABS sensors is faulty.
The more they get into specialized things like this, including laser ignition, the more I worry that I won't be able to be a backyard mechanic any more.
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The more they get into specialized things like this, including laser ignition, the more I worry that I won't be able to be a backyard mechanic any more.
When's the last you were able to backyard mechanic effectively, at least on a "modern" vehicle?
Most are locked down to the point that many of the smaller auto garages around my house have closed up because they couldn't afford to get every single piece of hardware/software to work on the new cars.
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Or even worse, they'll only ignite a certain brand of petrol :)
Doesn't worry me though. My car is diesel.
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There has been a lot of research in producing nanoparticles that absorb precisely limited wavelengths of light(mostly for nobler purposes). If you patented one with an unusual absorption pattern, and mixed it with your gas, you could ignite it with a laser tuned to emit in a suitably matched wavelength, while not igniting the normal stuff...
Re:Great... (Score:4, Interesting)
That's why I'm putting an open source engine management system in mine:
http://en.wikipedia.org/wiki/MegaSquirt [wikipedia.org]
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All I'm asking for (Score:2)
is a car with frickin' laser beans on its cylinder head?
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Has other applications (Score:3, Interesting)
There's another obvious application for this - detonating nuclear bombs.
Nuclear weapons require that all the charges be detonated simultaneously, within nanoseconds, so that the implosion squeeze is precisely symmetrical. (OK, A-bomb geeks, I'm ignoring asymmetrical designs and flying-plate systems here.) If the timing is even a few nanoseconds off, the core won't be compressed; it will just blow out on one side, and a "fizzle" yield will result.
The usual trick for this is to use an "exploding wire" detonator. Unlike regular detonators, which have an intermediate explosive to start the main explosive, exploding wire detonators do it in one step, by discharging a capacitor bank through a resistance buried in the explosive. This takes a very fast high-voltage high-current switch, and the traditional solution is a krytron, a gas-discharge vacuum tube from the thyatron family. There have been big flaps over the years about various countries trying to acquire krytrons, which aren't classified but are export-controlled.
Krytrons are 1940s technology. This laser ignition system could be its replacement. One big laser pulse pumped through fibers of equal length to each detonation point should do the job. And it's off the shelf dual-use technology.
I'm confused (Score:3, Funny)
Only problem I see here is... (Score:4, Insightful)
Sparkplugs cost like, uhm, a dollar.
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But if they are able to improve engine efficiency and bring the cost to a reasonable level, the math may work out.
Regardless, this is why we do research, people. Tons of technologies have been discovered by accident or adapted from less promising research. There doesn't always have to be an instant benefit for research to be worthwhile.
Wake me up when.... (Score:3, Insightful)
...they replace the fuel spray from injectors with heavy hydrogen pellets.
Lifetime? (Score:4, Interesting)
The problem with putting lasers in your engine is that it gets hot in there, and laser lifetime plunges drastically when you run them at elevated temperatures. I'm sure the dealers will love us having to replace our laser-plugs every two months, but no one else will.
(And if you're thinking thermo-electric cooling is the answer, that's going to use a whole lot of juice; don't know how feasible it is.)
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I'm guessing that's why they mention fiber optics in the summary, to pipe it in from a cold area (e.g. under the dash) and through the firewall.
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Can't imagine the kind of injuries you'd get from a high-power infrared laser shooting freely into a car accident due to broken fibre optics. Actually, I can. It's not pretty.
Laser-initiated ordnance systems (Score:4, Informative)
We used a similar system starting back in the late 1990s for initiating ordnance systems. The primary explosive would be doped with a small amount of carbon black to enhance absorption. One advantage was that specific equipment was required for proper initiation, which (in theory) made it safer.
Dynamite and a laser beam indeed.
Dependable (Score:3, Interesting)
So close... (Score:3, Interesting)
>> "So the spark plug could soon join the fax machine in the pantheon of antiquated technologies that will never completely disappear."
Aw, you were so close, but missed the mark. There are many other examples that you could have used and kept with the car theme. For instance,
Why not use microwaves? (Score:4, Interesting)
Re:misreading (Score:5, Funny)
Re:bs science as usual- and a waste of time/effort (Score:5, Insightful)
Only as much as they need to be an expert in fluid dynamics to change your oil.
this is not the way to make cars more efficient- spark plugs work great and im sure these lasers cant give any more power - the spark plug ignites the gas already, and it BURNS- how much more combustion could you get?
It is a good question as to how this would work any better but if you've ever spent any time under the hood you know it doesn't take much in the way of fouling or plug wire degradation to change fuel efficiency. If this system can avoid those kinds of issues it would make certain aspects of tune ups obsolete and would also increase fuel efficiency over a period when traditional plugs and wires would degrade but not to the point of seemingly needing replaced.
Re:bs science as usual- and a waste of time/effort (Score:4, Informative)
Degrading plug wires either cause a misfire, which is blindingly obvious and kills mileage horribly, or doesn't. There is no middle ground. Plug wire misfires happen maybe once or twice in the 300,000 mile life of a (japanese...) car.
Modern electronic ignition systems are fairly immune to spark plug wear until extreme circumstances, such as missing three tuneups in a row with standard plugs. Then you will sometimes get drivibility issues and lose 1mpg, tops.
Back in the days of points it was different, plug wear and point wear (mostly point wear) had huge effects on mileage between tuneups. These days, the effects are minimal at most.
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I've spent entirely too much time under the hood of a car(21 year auto mechanic), and you are entirely incorrect.
Degrading plug wires either cause a misfire, which is blindingly obvious and kills mileage horribly, or doesn't. There is no middle ground.
You are 100% full of shit.
I have personally had intermittent shorts in spark plug wires which caused them to fire fine sometimes. I found the problem by flexing the wire in question while testing it and watching the resistance go from a few kOhms to infinite.
In addition, plug wires can go partly bad, to the point where the resistance will be increased, causing a weak spark on some wires. You can find this problem by laying out all the wires on a table and checking their resistance. Longer wires should have
Re:bs science as usual- and a waste of time/effort (Score:4, Insightful)
the spark plug ignites the gas already, and it BURNS- how much more combustion could you get?
It's not so much getting more combustion, but making the combustion behave how we want it to. And there's a long way that can be gone.
But whether this has any real point compared to other fuels, such as diesel that have a big leg up on gasoline to start with, is up for debate.
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Because mechanics now are such experts on electricity. Or cars, for that matter.
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No, you do exactly what they do now:
When it is determined that there is no spark = replace the coil pack (laser sequencer), or replace the plug wires (fiber pipes), or replace the spark plugs (thingies that screw into the cylinders).
Now...this laser stuff may or may not be needed. But repairs nowadays = remove and replace the bogus part.
The coil pack
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You want uniform burn. This is the problem with ALL ICEs (Diesel and gasoline). Gasoline starts burning around the spark plug and propagates out, diesels start around the injector and go out. Ever seen a diesel spew black smoke? Or how about sit near an old muscle car and have it smell a bit like gasoline?
In an ideal world you combine the two cycles and get Homogeneous charge compression ignition [wikipedia.org] where everything in the cylinder goes BOOM with 0 fuel left over at exactly the same time.
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I'm assuming it's because gasoline is a helluva lot easier to light on fire. My experience from being an adolescent firebug was that gas burns easily, but very quickly, whereas diesel takes a lot more heat to get started, but burns more slowly, and probably releases more energy. I'm no chemist, but my understanding is that different hydrocarbons have different energy yields, and diesel is much more efficient, the tradeoff being a very different kind of engine.
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Re:Stupid question (Score:4, Informative)
Gasoline will auto-ignite just fine, it's just much trickier to control when it ignites than with spark ignition or diesel ignition.
Mercades has a engine in development called the diesotto [telegraph.co.uk] that does this.
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Gasoline is a very 'dry' fluid. It provides almost no lubricity. Diesel engines need some lubricity in their fuel to lubricate the very high pressure injection system (might be less of an issue with modern common rail systems and piezo injectors though).
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Diesel engines work without spark plugs -- they compress the air before injecting fuel; the compressed air is so hot that the fuel ignites by itself.
My truck has spark plugs, and every "consumer grade" diesel engine I have ever seen has them. So where did you hear of this non-sparking engine?
However, diesel engines require diesel fuel. They cannot use gasoline.
Actually several diesel engines can burn gas for short runs(like making in to a gas station). It is a good idea to go get a service check soon afterward because it can screw your system over, majorly.
Re:Stupid question (Score:5, Informative)
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Diesel engines work without spark plugs -- they compress the air before injecting fuel; the compressed air is so hot that the fuel ignites by itself.
My truck has spark plugs, and every "consumer grade" diesel engine I have ever seen has them. So where did you hear of this non-sparking engine?
Like others have mentioned, those are glow plugs, and they are really only necessary to start the engine when it's cold out. I've driven a Mitsubishi Pajero diesel that had no glow plugs. Works just fine, but starting at anything past -10degC is not fun. Takes about a solid minute of cranking and what looks like a volcanic eruption of black smoke before it'll decide to run. Luckily they're running on 24v so it can handle the extended cranking.
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My truck has spark plugs, and every "consumer grade" diesel engine I have ever seen has them. So where did you hear of this non-sparking engine?
Your diesel engine has glow plugs.
http://en.wikipedia.org/wiki/Glowplug [wikipedia.org]
Long story short: The glow plug's heat allows your diesel to start and then it maintains heat so that combustion can continue.
Really big diesels (commercial size) don't need a glow plug because air in the compression chamber stays hot enough to maintain the combustion temperature.
Re:Stupid Memes (Score:4, Funny)
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Spark plugs last just as long as they ever did in the same conditions (although some of the new coatings do extend life under given conditions.) The difference is that the engines are more reliable now, and more importantly not under the control of the driver. When you're not free to dump any quantity of fuel you like into the cylinder, it's a lot harder to end up burning up your plugs.