Changing Spark Plugs 2021 Mk4 Jazz Hybrid

[DavidPye]

Hi, my Jazz has done 38500 miles in the 5 years I have had it. Manual says no need to change spark plugs for 62500 miles. Should I be changing them after this time length? If so any good recommendations for videos of how to do it and what are the best spark plugs to use? Any advice would be great. TIA.

[Lord Voltermore]

The spark plugs will be iridium. Made with special materials  designed to last 62500 miles.

I am a bit confused . If you typically do 7.5K miles a year (38K over 5 years)  the plugs should not be due,or indeed  need, replacing  for another 3 years. 

Are you planning to change them, now?  If so are you sure you havnt been influenced by distant memories of how long 'ordinary' spark plugs used to last in days gone by? 

I dont know how to change the plugs.  I accept this knowledge may become increasingly useful as high mileage Mk4's enter  DIY servicing territory . Iridium plugs are expensive so I see the advantage of changing them yourself rather than risk an unscrupulous independent garage charging for a plug change that never happened.

However , despite doing some quite extensive car repairs in the past, personally I would treat the car to a full Honda service and plug change  when it reaches 62500 miles. Even if  other servicing has been by an independent garage or diy .

[DavidPye]

I would prefer not to replace them until the 62500 mark but in years gone past 5 years for plugs was about it and need replacing, so thanks for your detailed response and I will wait until nearer the recommended mileage.

[Lord Voltermore]

Some service items can deteriorate over time regardless of mileage. Brake fluid can absorb moisture. 
Engine oil needs replacing annually even if the car has only done a small mileage as infrequent short journeys on a cold engine is a harsh environment mechanically. (moisture doesnt get evaporated and dilutes the oil etc etc. )

But spark plugs are essentially a lump of ceramic and  special rare metals.  They can erode  due to miles, or maybe get contaminated with carbon, oil etc if the car only gets infrequent short journeys.  As  you do an average of 7.5K miles a year I dont see why iridium plugs shouldn't last 62500 miles.
In my opinion (and Hondas) 

[zdan]

I would inspect them and measure the gap to see if it's within spec and you really want to do it. If it doesn't misfire or shake and you dont have a drop in mpg, I wouldn't worry.

The downside is that I couldn't find the honda jazz spec online. What I could find is the new spark plugs gap that is 1.0-1.1mm for eHev engines but no luck finding the allowance (acceptable gap range).

Perhaps someone around here has some access to some workshop manuals for this generation of Jazz to clear things up.

[sebastiand]

I understand these specs are on the MaRIS but it is not cheap to use by an end user maintaining their own car.

Here I was planning on accessing in the future (after 3 years of warranty expire and I want to service myself) paying for 24hours and start printing to PDF as many procedures as I can.

Sent from my Pixel 9 using Tapatalk

[paulhipw]

My understanding of Iridium plugs is that they should not be adjusted due to the fragility of the points that they are manufactured with. I tried to check the ones that I recently purchased but they look very fragile and I realised there was no way I could safely adjust them.
I think you make sure the plugs you buy are for your engine and just fit them. I noticed the difference in performance when I changed mine, my car had done 80,000 miles and they were on the original spark plugs.

[Lord Voltermore]

This is what google  AI says about iridium plugs .

" Iridium  has an extremely high melting point, superior hardness, and high resistance to electrical erosion. This allows the plug to feature a much finer wire tip, concentrating voltage for a stronger spark and lasting up to 100,000 miles or more."

Or in other words, dont apply 20th century maintenance practices to 21st century technology .