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For those commenting about rotor 1 being tough to get to if one didn't have a swivel socket.... You just access the plugs from the bottom through the lower wishbone suspension. That method you don't even need any extension. Direct and sure attachment of socket and plug.
cheers.
Btw, NGK recommends against anti seize with brand new plugs.
You will only know if you remove the plugs and check them for fouling. If the center insulators look grey or black, replace them, or if you have the capability, clean them. If the center insulator is a white or brownish color, you're good to go. The center insulator is the key and any crud elsewhere is generally just a cosmetic problem, although it doesn't hurt to clean that up while you're at it.
Edit: the red area of the center insulator is what you want to see a whitish or brownish color.
I have a 2005 RX8 with just over 100k miles in Southern Florida. It sat from June to October. The battery died. With a new battery, the starter would spin, but the car would not start. The plugs were clogged up and wet fouled with perhaps a bit of oil residue. I replaced plugs (NGK), wires (NGK) and coils (NGK), cleaned the MAF sensor. Still no luck. It would start to fire, but would not start. So, I tested the compression (cold engine). The compression was 90psi for the front rotor and 95psi for the rear rotor. Again, this is not a proper test, but indicates the rotors are not totally shot, yet. I finally got the plugs cleaned good enough to get it to start using the fouled plug methods described elsewhere in this forum. However, it would not stabilize and would continue to die. Several times I was able to rev it up for a few seconds, but it would shut itself down. I pulled the new plugs. They were wet with unspent fuel. I cleaned the plugs and replaced them. Next I replaced the temperature sensor. Success! The car now runs fine. It appears the sensor was telling the ECM that the ambient temperature was extremely low (well below zero). This was directing excessive fuel to enter the compression chambers.
Many (including this forum and a local dealer) suggested the engine was probably toast. Fortunately, this was not the case. Hope this helps.
Never forget to clean the thread, nothing fancy as cheap as four groves on an old spark plug.
Also, no one can ever read a spark plug without cutting and removing central ceramic.
This pic is out of focus and for demonstration only. Note you need an otoscope too! Modified spark plug to use as a thread cleaning tool.
Modified spark plug to use as a thread cleaning tool.
You can a hacksaw or invest in the correct tool.
Last edited by motodenta; Feb 18, 2021 at 07:07 PM.
Reason: I should start to use advanced mood.
It is essential to tighten a spark plug to the specified turning angle or torque setting as torque directly impacts a spark plugs ability to remove heat from the combustion chamber. Over tightening can cause damage to the threads in the cylinder head and the threads of the spark plug, stress the spark plugs internal seal, or fracture the spark plugs insulator. Under tightening will prevent the spark plug from being properly seated on the cylinder head, resulting in insufficient contact with the head to transfer heat. Either of these would result in elevated combustion chamber temperatures, followed by pre-ignition and detonation.
Proper Tightening Procedure
Clean the spark plug threads and ensure the cylinder head is clean of debris.Screw in the spark plug finger tight until the gasket meets the cylinder head. Then tighten the plug as specified below:
With a Torque Wrench:
To find NGK's recommended torque setting, please enter the spark plug number in the search box. While viewing the part detail page, click on the "specs" tab. If a recommendation has been made, it will appear under the "Specifications" heading.
Without a Torque Wrench:
If a torque wrench is unavailable, finger tighten the spark plug, then use a plug wrench to tighten. 1/2-2/3 turn on plugs with a gasket. 1/12-1/8 turn on plugs with a tapered seat.
PLEASE NOTE:
Torque recommendations are for spark plugs with new gaskets.
If using anti-seize compound, use sparingly and reduce torque by 30%.
NGK has created their recommendations based on the general consensus of most engine manufactures. In the case of a discrepancy between the plug manufacturer and engine manufacturers recommendations, always default to the engine manufacturer.
