Mind to ask all sifus, how to actually see when the spark plug needed a change?? Is it the engine will vibrate or couldn't start at all????
Normally how long the life span of the spark plug? 2years??
I had my share of spark plug fouling on me before. At the very beginning, u'll encounter misfire during some of the engine start up. Then it gets worse to misfire on nearly every engine start up. Eventually, the engine will start to vibrate violently and the car felt very sluggish and not wiling to rev. Upon diagnosis, found out only 1 of the spark plug failed lol.
In my case, i was using iridium plugs and the mileage hasn't even reached 20k km however i was running on a na with bot thus yea the plugs may failed even sooner than expected
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Anyway changed to laser iridium plugs and it was good for all the way(2 years plus)
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