Spark plug change intervals?, Are plugs time "sensitive?"? Options

[draganc]

Let's assume your engine is well running.
How often do you have to change the plugs if you drive only 4-5k mls per year?

Any difference between older air cooled and h2o engines?

Thanks for the inputs!

[Tom_T]

Usually that's due to inspection when it shows too much build-up or fouling, etc. They can be sand-blasted for minor normal build-up, but get a spark plug guide online with pix to show what the different deposits mean.

At that low rate plugs can go a long time, but probably are best changed at the owners manual recommended tune-up interval time or miles. However, they're pretty cheap for the OE recco'd copper plugs in the 914s, so not a wallet buster if you replace them more often.

We do them on the factory schedule for our 2 DDs (85 BMW 325e & 88 VW Westy) with 2-3000+/- mi/yr now that our kids are grown & gone, & what my guy did with my 914 when it was a DD at a more avg. 7-10k+ per year. He was factory trained on 914s & was Circle Porsche's specialist on them before he started his own shop in `72. Later this year will be 40 years with him this summer, since he PPI'ed several 914s for me & worked on my 914 & others since then - 40 years & he knows his stuff!

Cheers! (IMG:style_emoticons/default/beerchug.gif)
Tom
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