Spark plug replacement surprise

I notice there is still some 3/8 hose in kit along with some 5/8

- 1 Oil catch can
- 135" of 3/8" polyester reinforced oil, fuel and chemical resistant hose
- 1 Drain valve
- 20" of 5/8" PVC drain hose
- 5 zip ties
- 3 1/4"-20 X 1/2" stainless steel bolts
- 3 1/4"-20 Nylon insert lock nuts
- 2 Stainless mounting brackets
- Installation instructions are available in our support section
- Shipping is free in the US & our Hassle Free Lifetime Warranty is included
 
Some are 3/8 but the hose off the separator is a 3/8 on the 2.5 mazda 3, and 5/8 on cx5/6
 
It just doesnt make sense to me. How could a spark plug that is made the same as all other spark plugs be used as a sensor to detect knock/pre-detination etc.. ? Does knock create some sort of Electro Magnetic Pulse or maybe excess heat that heats up the spark plug material that changes its conductivity characteristics?

.................

Resistance across a spark gap changes with pressure. So does the relationship between current and voltage. Spark knock dramatically increases cylinder pressure and does it suddenly.
 
I'd like to jump in and ask if you guys use any anti-seize compound on new plugs? I've read many different opinions about it which fall into 3 categories:
1. Do not use anything
2. Use any anti-seize
3. Use anti-seize for aluminum.

Great thread BTW.

I used aluminum anti-seize on the new plugs in my MX-5. Removing the original plugs at 6 years and 80k miles was excruciating. They were stiff and groaned and creaked coming out.
 
I used aluminum anti-seize on the new plugs in my MX-5. Removing the original plugs at 6 years and 80k miles was excruciating. They were stiff and groaned and creaked coming out.

Mine did none of that at 88K miles (albeit only 3 years). They also showed ZERO evidence of anti-seize on the threads from Mazda, FWIW. I did the plug change as soon as I got home. Hot hot engine etc. Block fully expanded and heat soaked. This is why: https://www.engineeringtoolbox.com/linear-expansion-coefficients-d_95.html
 
Today I planned to replace the spark plugs on my 2013. I'm at 60,000 miles. The severe service schedule says to replace them at 75,000 but I do most of my work early.
Not wanting to spend $25 or more per plug on the OEM ones, I went to Amazon and bought the Bosch Platinum that it said was a match for my car.
So I grab the 5/8" spark plug socket that I've used on various cars for about 30 years and head out to the car to remove the OEM plugs. No luck. The socket is down all the way but it just spins freely, not grabbing the plug. I spent a long time trying to figure that out. The web says that 5/8" is standard. The 5/8" socket fit perfectly on the replacement plugs I got. Finally I find a website that refers to using a 9/16" socket on the CX-5. I found a long one of those in my tool box and it did the trick. If you search for a 9/16" spark plug socket they typically refer to certain Ford Triton engines only. Go figure...

So my warning to you is:
1) You most likely will need to buy a new 9/16" spark plug socket because your 5/8" one is too big.
2) When you shop you may be told to buy the wrong size spark plug. You want a 12mm thread size, NOT a 14mm thread size. I shopped online at various national retail chains and got mixed results. Some selected a correctly sized plug (Champion and Denso are the only ones I could find) and some sites selected a too large plug. One site told presented me with both 12mm and 14mm options.

My OEM plugs are the Mazda PE0118110.

Great tip! Thanks for sharing!
 
Back