Owner reviews for spark plug

Mazda skyactiv engines are beyond easy to do. Did it on my 16 Mazda6 in 20 minutes. Probably can be done sooner if the spark plugs are pre-gapped and you're not OCD.

Did 3 of the 4 of them on my wife's CX-9 and it took way longer, due to the turbo parts on top and the engine being set, so far back (vertically challenged and T-Rex arms). Dealer ended up doing the 4th one (driver side plug).

Rock Auto has good deals on the NGK plugs, that are basically the same as the OEM ones.

Torque wrench is unnecessary for plugs. I have several and have never once used them for plugs. 1/4 turn past hand tight is all you need. Good plugs like ngk laser iridium or ruthenium hx will run you less than 40 bucks. A small single use packet of anti seize compound and a 6 pack of your preferred beer. Less than 100 bucks all in and an hour of your time.

NGK plugs have instructions on the package and do not require a torque wrench. I have a torque wrench, but I do not use it for my spark plugs. It's just hand tighten until it makes contact - then turn it however many turns they say with your socket to fully seat it (usually like ½ - ¾ turn or something like that).

You don't need a torque wrench, NGK plugs have a crush washer and specify half turn past initial contact. Did my Mazda 3 with no issues. I have a torque wrench and didn't use it.

The tools aren’t expensive. Yes I use dielectric grease but not anti sieze on the threads (only because BMW orders us not to). Easy job for most cars.

Harbor Freight has the torque wrench you’d need for $19.99 the Pittsburgh 3/8" drive and a 3/8" drive extension set for $16.99. I’d also grab a magnetic spark plug socket from AutoZone for $14.99 (just go straight for the magnetic one, it makes life way easier).

For the spark plugs themselves, I’d stick with NGK, but make sure it’s the correct spec for your car, since they make different cx5's, some being NA and some being turbo.

As for the "paste," some people put antiseize or dielectric grease on the threads to make future removal easier. I personally skip it because I want zero chance of anything getting into the engine, plus grease can amplify the torque applied with the wrench, which is bad. I’m hoping this is what you mean by paste?

If you do it yourself, the first time costs roughly $100-120 for the tools, and still is about half of what the dealer is quoting. After that, you just pay for the spark plugs themselves for future changes, which brings the cost down to around $50-70 per change since now you'll have the tools.

I replaced the plugs with DENSO 5358 roughly 10K miles ago.

Right before i changed the map I also swapped spark plugs (brisk er12s). Since it started the rough vibrating, I’ve inspected spark plugs and coil packs, changed the coil pack grounding to a ground kit, cleaned the MAP sensor, and even tried throwing some liquimoly valve clean in it.

I changed the spark plugs on my X5 with Bosch ones. My mechanic showed signs of being upset with me for not bringing the genuine BMW ones... Fast forward to a week ago - the car throws a check engine light and OBD scan shows faulty oxygen sensor heater circuit. My mechanic linked this to the Bosch plugs, suggesting they might not be the correct type. I ended up replacing them with genuine BMW plugs and an O2 sensor, which cleared the codes and improved power. My learning is that Bosch has many SKUs, and it's hard to ensure the exact OE part number, potentially leading to incorrect plug types (e.g., 'double platinum' instead of 'laser iridium') for BMW, costing more in the long run.

autolite, worst spark plugs in the world. I'm tired of customers asking for cheaper plugs and they cause misfire