bayridgeguy

Folks,

My 2009 Q5 is coming up on its 55K maintenance but not my miles-by time. I only have 30K miles on it. Based on your experience, should I be replacing spark plugs this time around?

If I understand the Audi document correctly, is this the recommendation for my 09 Q5?

Replace at 55,000 miles or 6 years, whichever occurs first. Then, every 60,000 miles or 6 years, whichever occurs first.

Thanks!

MP4.2+6.0

And yes, if you are careful with your maintenance, you can hold off until 55K real miles. Plug wear is mostly number of ignition sparks, which of course is back to miles. If you burn oil or often don't drive long enough to warm up motor, then maybe want to keep up with it more aggressively. But assuming no fouling type issues or driving profile, can just keep going as a practical matter. If under extended AudiCare by chance, the net is gets done anyway. BTDT on some major service intervals that came up well short on miles on prior Audi's.

lmariorod

I wouldn't worry about the plugs. I changed mine at 76k on our '10 Q and they still had lots of life left.

Then again, the wife did lots of highway driving at constant 70+mph, something that is tough to do on the Belt Pkwy, Grand Central or L.I.E.

Knowing those roads, I'd be looking out to replace my brake fluid every two years because of the stop and go. And keeping a close eye on suspension and brake parts.

Redd

The plugs only "wear" per spark, but they are also subject to heat cycling and thermal stressing of the insulation. If the low mileage reflects long hours at low speeds, it would still reflect many engine-hours.

More than the plugs, the high voltage ignition wiring can also be affected as the "rubber" breaks down from age, ozone, and heat, not just per-spark. These can be tested with a simple common ohm meter for objective standards.

So, probably you don't need to change things based on time alone, but they should still be inspected for aging and condition. Spark plug tips will tell you if there are deposits fouling them, as well as abnormal wear.

Of course, pulling these things and putting them back after an inspection consumes the same amount of labor as changing them. Depending on what you have to pay...the economics vary.

bayridgeguy

thanks folks. my driving is mostly around the city - traffic lights, stop and go...sounds like i maybe ok depending if i want to air on the side of caution or not...going to look into the cost of doing it...

MP4.2+6.0

? High voltage ignition wiring? Yesteryear==>coil on plug Audi norm for years

Redd

My bad! I try not to look under the hood until the warranty is up.(G)