vs
Spark plug Denso or OEM Mazda
Ignition coil most likely. I have done many dozens of them. Takes about 2 minutes to replace.
Pros: easy to replace
I recently got Denso (OEM) from my local o’reillys cheaper than the dealer (~$80).
Pros: cheaper than dealer
Bro ABSOLUTELY do the spark plugs yourself. I bought oem Denso spark plugs from Napa Auto for about $180. Then all you need is a spark plug socket w/ swivel head, 10mm socket, 12mm, a couple extensions, needle nose pliers, dielectric grease, and a pick to make life easier.
Pros: save money, easy job
Cons: time consuming for beginner
Denso iridium spark plugs
Pros: improved engine performance
Vehicle:
Toyota
New Denso Platinum spark plugs. Car drives great, no codes, no sputtering or stalling or hesitation.
Pros: car drives great, no sputtering
Vehicle:
Toyota MR2
Fitting a decent set (Denso or NGK) of iridium plugs is also worthwhile.
Pros: worthwhile
Vehicle:
Subaru Legacy
Just did mine at 69k. Felt like a small pickup in performance.
Pros: pickup in performance
Vehicle:
Mazda
Mileage: 69000 km
That price at 63.5k miles isn't bad imo. I spent roughly that same amount for my 2017 back in 2019 with around 40k miles (64k km). What's the service history look like? Have spark plugs been replaced, belts checked, engine oil changed at least 10-12 times by now? How are the pads and rotors?
Vehicle:
Mazda
Mileage: 102200 km
I’ve had several Denso plugs do this on a couple Camrys I service, and our own. All 2.4 cars. Caused tow ins for both husband and wife’s cars. I’ve fired denso as a spark plug provider, too many failures.
Pros: null
Cons: too many failures
Vehicle:
Toyota Camry
I wish my Toyota 4Runner spark plug service was that cheap in the Toyota dealer. I was quoted $800 parts + labor for OEM Denso.
Pros: OEM Denso parts
Cons: expensive parts and labor
Vehicle:
Toyota 4runner
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Which spark plug to choose — Denso or OEM Mazda?
If choosing spark plug across many manufacturers, check the part ranking. If your choice is down to two brands, the PartReview part comparisons help.
We compare spark plug across these categories:
- PR Score.
- Overall ranking.
- Vote balance.
- Average rating.
- Number of reviews.
- Feature ratings.
- Car owners’ choice.
Which spark plug are better — OEM Mazda or Denso?
In March 2026 on PartReview, spark plug OEM Mazda and Denso were roughly equal.
- Denso received a PR Score of 78 out of 100, and OEM Mazda scored 95 points.
- Denso ranked 2 in the overall ranking, and OEM Mazda ranked 6.
- The average rating is higher for OEM Mazda (4.5) than for Denso (3.9).
-
Spark plug OEM Mazda have better feature ratings than Denso:
- Starting - owners believe, that this property for OEM Mazda is better than Denso.
- Idle - drivers claim, that this property for OEM Mazda is outperforms Denso.
- Acceleration - reviews suggest, that this property for OEM Mazda is preferred to Denso.
Which spark plug are more popular — Denso or OEM Mazda?
In March 2026 on PartReview, spark plug Denso were overall more popular than OEM Mazda.
By vote balance, spark plug Denso surpassed OEM Mazda:
- For Denso, the ratio of positive (447) to negative (123) votes is 324 votes.
- For OEM Mazda, the ratio of positive (41) to negative (2) votes is 39 votes.
By number of reviews, spark plug Denso surpassed OEM Mazda:
- For spark plug Denso there are 184 reviews: 137 positive, 18 neutral, 29 negative.
- For spark plug OEM Mazda there are 14 reviews: 13 positive, 1 neutral, 0 negative.
Which spark plug do car owners prefer — Denso or OEM Mazda?
In March 2026, according to PartReview, spark plug Denso and OEM Mazda have not taken top places in car-specific ratings. You can help by adding your review about these manufacturers.
Other comparisons of spark plug
If this comparison didn’t fully answer your question, there are many others on PartReview.
For example, comparisons of spark plug Denso with: NGK, Bosch, Autolite, Champion, AC DELCO, BRISK, OEM Volkswagen, OEM Toyota, Motorcraft, OEM FORD.
Also available: comparisons of spark plug OEM Mazda with: NGK, Bosch, Autolite, Champion, AC DELCO, BRISK, OEM Volkswagen, OEM Toyota, Motorcraft, OEM FORD.
You can also see who is better among other spark plug manufacturers: Bosch or NGK, NGK or Denso, NGK or Autolite, NGK or Champion, NGK or AC DELCO.