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Hi fellas,

As some of you may already know, I was having spark plug fouling issues (and still am), but I had a new experience yesterday.

I purchased a new set of NGK BCP7RES (I think that's the code) gapped to 0.8, EXACTLY the same as the ones I currently had in the car.

Now, every month or so, I replace the spark plugs because my car runs better, but this time, it was different.

I usually cap the spark plugs down to about 0.75 because thats what they were since the tune. However, this time when I put the new ones in, the car was misfiring all over the rev range!

So, I measured the gap on the old spark plugs and they were the same gap as the new spark plus (0.75) so I wasn't sure what the problem was. Nonetheless, I put the old ones back in and now the car is running fine again.

Has anyone else encountered this problem? COuld something have gone wrong when I was gapping the spark plugs (although I dont see why it would because I did it like 5 time before)?

ANy help would be great.

Cheers

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there is no such thing as a product with a 0% failure rate. think about the amount of spark plugs NGK sell... you were just the unlucky one who got a dud spark plug. its probably only one spark plug that is faulty.

put one spark plug into your car and drive it for a day, if you are not missing change the next one.. if its okay the next.. untill you find the dud one and then buy a new one or take it back for replacement :)

Hi, just thought I could help a bit... If it is misfiring then it is same as the problem I have now... I'm going to replace my coil packs to splitfire coil packs... I think this will get rid of the misfiring and my rough idle.. :)

To find the dud one, check them on a lawnmower, take the mower plug out, use a jumper lead from the spark plug lead connection to the spark plug thread [so you have contact] then pull the starter cord. The one that doesn't spark is the dud.

Another quicker way is to use a multimeter and check for discontinuity between the spark plug body and the firing tip - this sometimes doesn't work, but it is a quick check and if you find one that has circuit then it is the dud one.

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