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24

Spark plugs are normally a wear and tear kind of part instead of an "all or nothing" kind of failure. Over time, they get worn or build up deposits from years of use and they become less effective and efficient. I have rarely ever heard of a spark plug failing 100% all of a sudden. Over time, it would contribute to reduced gas mileage, rough idle, and ...


21

Copper conducts better and is generally used in higher-performance/modified engines. In dedicated race cars resistor-less copper plugs are used. Iridium and platinum plugs are chosen for their longevity only. You shouldn't gap iridiums because of potential damage to the tips. For that reason and their inferior conductivity, they aren't used in modified ...


17

Your owners manual should tell you how often to replace the spark plugs in addition to that I would inspect the spark plugs every 5000 miles. Spark Plug Conditions Normal operation will show a light tan or gray color. The gap clearance will be slight with very little deposits on the insulator tip. A plug that indicates replacement will show ...


16

If you keep driving it that way for very long, the fuel that's pumping through the non-firing cylinder will contaminate the catalytic converter. That can result in the catalyst overheating and melting, possibly blocking the exhaust in the process (BTDT and cats are not cheap...). If you're really having a bad day, the cat could theoretically catch on fire ...


13

I had a spark plug fail completely and another one hardly work on an old 5 cylinder Audi GT coupe sport. It was as rough as a badger, but you could still drive it back home to sort it out. Certainly not fatal:-)


9

The main difference is the material that the 'tip' of the spark plug is made of - normal ones are usually copper, whereas the other two have tips made out of platinum or iridium. Platinum and iridium tips tend to last longer - copper tends to erode over time so the spark plugs wear out - plus they're slightly better conductors and can produce a spark under ...


8

They really are that simple - as long as you torque them correctly, there isn't a lot that can go wrong. They are designed to be as straightforward as possible - they don't require calibration, measurement etc. Make sure the connector is securely on the top of the spark plug, and make sure you don't get oil or grease on the contacts. And do them one at a ...


8

Yes. Very gently tapping to decrease gap is fine. Most spark plug gap measuring tools also work to gently pry the electrode back. The key is to be careful. It does not take much force to make the adjustment and the insulation around the electrode can be damaged if handled improperly.


8

Mostly replacement is preventative maintenance. Eventually they'll get cracks that moisture can get into, etc. If they test good, they're probably fine for the moment, however, at their age they could develop problems any time. On my '91 Toyota, I've been through several sets now, and have to say that in my case, OEM is the best. I've tried other brands ...


8

First, think of the possible failure modes: Spark plug is clogged with carbon or has an isolation error - it conducts current, but doesn't generate sparks, because the current flows through the carbon from electrode to electrode. Break inside the plug, e.g. broken / worn electrodes - plug doesn't conduct (and of course doesn't generate sparks) Cable has a ...


7

Check the other end of the wires to make sure you did not loosen them. Your wires could be going bad and moving them around made the problem worse. Would not hurt to replace them as well. Also it could just be a coincident with the spark plugs, it could be a fuel issue or a problem with your distributor. Although, this is less likely than the first two ...


7

Note that while it's common to re-gap copper plugs, the platinum (and other more exotic) plugs that I've seen usually say that they're not to be re-gapped. If you choose to re-gap them, the risk is possible breakage (potentially during operation) as some of those other metals are more brittle than copper and don't appreciate being re-gapped.


7

The oil pan never gets hot enough in normal operation to soften the metal of the oil pan or the drain plug, and any thermal expansion at that temperature also shouldn't be much of a concern. For me the ideal temperature is maybe about 20-30 minutes after a drive, or when I can safely put my hand on the drain plug for a few seconds. The oil is still warm ...


7

My best bet is that the spark plug is too long in the first place. I don't know what the stock spark plug should be for your bike, but the NGK you are showing may/may not be completely within spec and therefor is extending down into the cylinder longer than the spark plug should. If the bottom end was worn out enough to allow the piston to travel that far up ...


6

Before doing anything else, get some penetrating oil. Reducing friction in the threads will dramatically reduce the amount of twisting force required to remove the stuck plug, making the job way easier & reducing the chance of making things worse (i.e. breaking off a screw extractor!) Follow the instructions on the container, or just spray around the ...


6

A couple ways to go about this, depending on the exact situation: If the ceramic stem is broken, and you can still fit a deep socket on it, go with that. If the nut itself is stripped so much that you can't get a socket or an open-end wrench on it, or if the nut is broken, you should try using pliers to remove the spark plug. You could also try something ...


6

I think your example is running pretty good, but may be a tad on the rich side. Nothing much to worry about. If it were running a tad bit leaner, the plug would have more of an tan/ash color to it. When reading the plug, don't pay as much attention to the bit at the top of the threads. This area is prone to have some minor carbon build up no matter how well ...


5

The most likely cause is the valve cover gasket. You can try to tighten the bolts that hold the cover, but most likely the gasket or seal needs to be replaced.


5

Gasket sealant is always good, but not necessary. Sealants are different, so ask the guy at your local auto parts store for sealant for the valve cover gasket. The difficulty levels vary with this, however. For example, I have an older Nissan Hardbody truck with leaking valve cover gaskets. The new gaskets are cheap enough, but removing the valve covers ...


5

Buy a can of good quality penetrating fluid (not WD-40, which is designed as a lubricant). Spray plenty of it into the plug recess, and leave overnight. Repeat this two or three times. Using a proper spark plug spanner (with the little rubber insert to grip the plug properly), try to rock the plug back and forth, tightening then loosening. Eventually, with ...


5

I like to put a little anti-seize on the threads before putting the new plugs in. That helps ensure the plugs come out nice and easy the next time you have to do it. It doesn't need very much and make sure not to get any of it on the electrodes.


5

The two biggest risks I can think of are fire, destroying the catalytic convertor and possible exploding a muffler. The arcing of the plug wire could ignite the underhood insulation. The extra unburned fuel could ruin the convertor, the fuel could collect in the muffler and ignite rupturing the muffler. All these are worse case scenarios if the distance is a ...


5

If you are suggesting there was oil inside the head where the valves/cam(s) are located, this would be perfectly normal. If you are saying the oil puddles are outside of the valve/cam area, this isn't normal, but should be taken care of by you putting a new valve cover gasket on the engine. I would say, clean up the entire work area, complete the replacement ...


5

It doesn't hurt things to test the spark or spark plug by doing so. You obviously don't want to run it that way for long. Most fuel injected vehicles have a fuse in the under hood fuse box which is for the fuel injectors. If you pull that fuse, the injectors won't fire, though everything else still works just fine, like the firing of the spark plugs (as long ...


5

Theory It sounds as if the starter solenoid is getting 'stuck' due to low voltage. That is the second buzzing noise. The high pitched sound is your fuel pump priming your system and is normal. Perhaps the rain created a grounding situation that drained your battery a bit. Regardless of that speculation, here is the fix. Charge the battery. I believe ...


5

Yes you can. Obviously you'll be at a reduced power level, but no problems should occur from doing this. EDIT: While I believe this is a "plug on" application, you'll want to ensure your coil is not connected either. I doubt it will be down in the hole, but you don't want to have the coil attached to the wiring harness without it being able to throw ...


5

The spark plug heat range refers to how well the center electrode conducts heat to the head. A hot plug can't conduct the heat very well that is what makes them hot, they can't cool themselves. A cold plug conducts heat well, by moving heat away quickly the spark plug stays cool. The need to control the temperature of the center electrode comes from ...


4

One more option: If you tried taking the spark plug out of a hot/warm engine and the plug broke off between the lug-flats and the lug-threads (both non-technical terms), you may be able to use a screw driver or chisel to gently tap the remaining portion out. Here's why: When your engine is hot, the spark plug holes are compressed due to the expansion in ...


4

No one has mentioned vibration yet. When one of the spark plug wires went 'bad' on my Chevy LS1, the spark plug failing to fire immediately translated to regular vibrations that changed frequency with RPM and became especially bad at idle. Replacing the wires (and spark plugs) eliminated the vibrations completely.


4

It should carry on running, albeit somewhat lumpy. I've seen a car (a 6-cylinder BMW) spit out a plug on the motorway, it carried on running quite happily, just got noiser and lost some power (as you would expect!). The owner pulled over at the next exit, found out what had happened and drove to the nearest parts shop to get a new plug.



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