The Do-It-Yourselfer's Guide to Replacing Mitsubishi Spark Plugs

The spark plugs in your Mitsubishi start to go bad, and you'll know it by the signs: trouble starting, engine misfires, rough idling, and power loss, most of the time. Sometimes, you might notice your ride having trouble speeding up or burning more gas than usual, too, or its fuel economy worsening, strange sounds coming from its engine (like knocking, rattling, and pinging), and even black smoke in its exhaust. Most often, though, that they're faulty, you'll be able to tell by the plugs' leads being wider than usual or corroded, by the plugs not conducting electricity as well (or at all), or by the ends of the plugs seeming oily or greasy.

Whatever you end up seeing, though, you let a spark plug fail, and you'll end up with engine and fuel system problems. You know what that means, too: costly repairs, sure to follow. Our advice: replace any that are trouble sooner rather than later.

It's a good thing you came to us here at Mitsubishi Motors North America for advice on what to do, exactly. You can swap out the old for the new DIY -- and pretty easily, in fact. If you're looking for more specific directions on how, though, your best bet's to take a look at your owner's manual. But if it's pointers you need -- perhaps not always included in a maintenance checklist, here's a shorthand.

Replacing Your Mitsubishi Spark Plugs 101: Six Easy Steps

1. Grab the tools you'll need. For one, a spark plug socket (most commonly, that a 5/8-inch or a 13/16-inch). Secondly, a gasket for the tip of the plug, plus a gap tool (for checking spacing between the electrode and ground). Thirdly, a screwdriver, and some anti-seize lubricant (to make the plugs easier to remove next time you have to change them).
2. Let the engine cool off. Work with a hot engine, and not only can you damage a plug's threads. You'll also end up getting burned.
3. Disconnect the battery. A spark plug's practically part of an engine’s electrical system. So, messing with anything connected even indirectly to the battery's terminals can cause short-circuits -- and which point, you'll likely have to do a battery replacement, at least.
4. Remove the plugs' wires. Otherwise, remove their coil-on-plug connectors, if they have them. (Older Mitsubishi models generally have wires, which connect their spark plugs to their ignition systems; newer Mitsubishi models, in contrast, have coil-on-plug designs, where each plug has its own ignition coil.) In the case of having wires, label each to make sure you can reconnect them in the right order when you put in a new plug. Then, grab the boot over top of the plug and pull them straight up to remove them. In the case of having coil-on-plug connectors, label each for reconnection in proper order when you install the new plugs. Then, press the locking tab on each plug with the screwdriver to release it, and pull the connectors off.
5. Gently unscrew the plugs with the socket. Go counter-clockwise, but not too hard, or you'll crack them, and pieces may get stuck in the engine. Be sure to keep any debris out of each plug hole as you lift each plug out.
6. Put the new plugs in. First, rub anti-seize lubricant on the threads of each, then insert and finger-tighten them, giving them final half-turns afterward. (Don't cross-thread or force the plugs; a damaged spark plug will only end up broken, and if one breaks while the engine's running, it can mean serious cylinder damage, and that replacement's one expensive fix.) Now, reattach the wires or connectors, and then reconnect the battery, in the correct order.

If you're looking to buy genuine OEM replacements, shop with us: our spark plugs are Mitsubishi-made, and so, top-quality; they'll fit your engine and work right with it the first time. Plus, they won't void any factory warranty your ride has, like some aftermarket spark plugs can.

Take advantage of competitive prices and fast US shipping; order now. Contact us if you have any questions!