Plug change interval

[Storage Man]

Hey guys and gals,

Doing my custodial work in getting my 86 3.2 on the road this weekend after not driving for a year or so.
Was reading in my service manual the recommended plug change was, 30k miles or “at least every two years.” ???

I put about 1000 miles on my 75k garage queen a year. It’s bee at least four year since I changed them out.

Thoughts?

[FrankM_]

I do change them every 2 years irrespective of mileage (doing approx 2K miles/year) since its only a 10 Eur cost per 6 plugs. That's not really adding significant amounts to the running cost.
The yearly oil change is much more expensive per mile driven if I can say so. Buying 11 liter of high-quality oil (>100 Eur for 11l) and oil filter is where I would question the real necessity...

[Storage Man]

Agreed Frank. Thanks.
What are you using to get them out?
Can’t remember the tools other than the 3/16 socket

[HarryD]

Originally Posted by Storage Man

Agreed Frank. Thanks.
What are you using to get them out?
Can’t remember the tools other than the 3/16 socket

More like a 13/16" socket.

If you have the factory toolkit with the sparkplug wrench, it works great! It is what I use on my car.

also, while I can see an annual oil change (absorbing water, products of combustion causing corrosion), I do not see the point of using time for spark plugs. It is not like they degrade by just sitting there. I would use a mileage or running issue to trigger a change.

[Storage Man]

Hey Frank
Totally forgot about the plug tool n the tool kit.
It does work Great.
Pulled a plug. Pretty clean. Might hold off.

[Storage Man]

Originally Posted by Storage Man

Hey Frank
Totally forgot about the plug tool n the tool kit.
It does work Great.
Pulled a plug. Pretty clean. Might hold off.

[Storage Man]

Originally Posted by HarryD

More like a 13/16" socket.

If you have the factory toolkit with the sparkplug wrench, it works great! It is what I use on my car.

also, while I can see an annual oil change (absorbing water, products of combustion causing corrosion), I do not see the point of using time for spark plugs. It is not like they degrade by just sitting there. I would use a mileage or running issue to trigger a change.

Thanks Harry, I’ve added the Bently’s manual page photo on the two years..??

[GH85Carrera]

That seems really excessive. I know of lots of cars (not 911s) that go decades on the same plugs. In the days of carbs and bad running engines I can see it as a good idea. I drive mine enough that I change the plugs every few years anyway, but it is not a regular maintenance thing.

[Storage Man]

Glen!
Good to hear from you.
I’ve ready many of your posts over the years. Especially when I first joined.
Hope all is well.

I agree, I pulled my plugs anyways and took a look at them and cleaned, they seem to be fairly new looking will skip that this year I believe .

[Koizumi]

These threads always remind me how dope the OEM sparkplug tool is... It’s a weird oddity that is engineered perfectly.