Spark Plug Removal

What Chris_Top_Her has said does have his base. OVT (OrangeVirus Tuning) had posted following comments several years ago here.

OVT said:

Without getting into too much detail...you guys really...really..really want to use OEM plugs....

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OVT said:

the reason is because the ECU uses the ignition coils, which measure a resistance across the OEM plug for pre-ignition, and extremely low levels of knock retard the knock sensor cannot pick up, along with that it gives the ECU individual cylinder information, the spark plugs are actually used "as a sensor."

How it works exactly is proprietary information that I am not willing to share, you want to use OEM plugs.

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I get my sparkplugs from Rockauto.com
In fact, I just recently replaced my Miata (with 60,000 miles on the odo) plugs with NGK Iridiums.
Rockauto has a great selection that almost always includes OEM at discounted prices.

Just make sure you gap them to the factory requirement.

yrwei52 said:

What Chris_Top_Her has said does have his base. OVT (OrangeVirus Tuning) had posted following comments several years ago here.

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Im not sure what the price for spark plugs is in USA but in Australia 4 genuine Spark plugs for cx5 cost you roughly $150 AUD for a set whereas I can get NGK ones for $60. You try to convince a customer to buy genuine ones. The reason they are not servicing their cars at the dealership is because of these prices. And if that tolerance number for as spark plug was very different, it would be a very known problem and NGK wouldve made special spark plugs just for mazda. But case is that the difference is not relevant or not that far out of spec thus no issues with aftermarket plugs. And I guess chances for this to happen is probably 1 car out of 1000.

If I had the OV tune then yes I'd probably get OEM plugs. Otherwise........

Zero, zero, zero issues with NKG plugs that are marked exactly the same as OEM except for the Mazda logo.

$4.99 and free shipping. Choose from 'other choices' so you don't have to buy $25 bucks of stuff for the free shipping.

https://www.amazon.com/dp/ (commissions earned)