When to replace spark plugs
 

Is there any rule-of-thumb as to when to replace the spark plugs? I've had my 2004 RX-8 since new and it still has the original plugs. That might sound bad, but it only has 29,800 miles on it. I did replace the coils last year. And what about the spark plug leads?

If only there was a reference document somewhere that listed detailed maintenance information and recommended intervals at when to perform. :dunno:

I'd give her a threat and change them anyway, those last set of spark plugs and leads owe you nothing, you got good use out of them.

I changed my plugs, wires and coils at 25k miles. Better safe than sorry, cats aren't cheap.

I change plugs every 20k and I think I changed the leads at 30k-ish with the coils just in case. spark plugs are easy enough to change and the general recommendation is about every 20k.

Posted From RX8Club.com Android App

I've heard rumors of such a thing. There's a legend that it says to change spark plugs every 36,000 miles. But one can't base maintenance on legends. Only what people might post on a web forum.

Ken

I'd rather replace all 3 (coils, plugs, and wires) at the same time, rather than replacing each with a certain time...

I had the spark plugs and leads replaced today. I'm glad I did. The spark plugs looked pretty worn, plus the L (leading plugs had light brown crap in at least one groove (I don't know what the 4 grooves cut on the circumference are for). Also,
one plug had heavy rust on the contact where the lead plugs on.

So, all new NGK plugs and NGK lead wires. Starts and runs like a champ!

I am actually just waiting for my plugs/coils/wires in the mail. From what I remember reading around this forum you should always change all 3 at the same time (after any sign of ignition failure symptoms)

had to go with Ebay thanks to a weak dollar and limited funds. I HAVEN'T EVEN DRIVEN MY 8 YET just fixing her from previous owners, car has been haggard but I'm still counting the days until I can splurge and buy BHR coils