This seems a bit vague to me so I thought I'd ask. When do you change plugs on the .1 TT? Seems that tuned cars may need them in 20k. I believe the maintenance manual suggests at 40k. Is that strictly mileage driven or should they be changed on a time interval basis? Or should they simply be changed when performance is effected?

 

Generally, a lot of tuners advise you to change the plugs once you tune the car. I changed my plugs at the same time as I installed the exhaust, diverter valves, and a couple bad coils that were throwing a code.

Intervals of 20k for changing them thereafter sounds fair but I have not reached that mark yet so not too sure.

 

25-40k

 

and or 5 years

 

So, time based as well? I've looked at plenty of used '07's, but haven't seen a lot of cars that have had plug changes. Is 5 years in the service manual or a personal recommendation? In looking at cars with 20k miles, I'm thinking a plug change is a 40k event (as per the manual, I believe). At up to $1500, it's a pretty significant service event.

 

When this came up with my 996 Turbo the techs told me that while the owners manual lists spark plug changes based on miles and elapsed time that sometimes one or both are changed by Porsche.

For a stock car the best advice I can give you is check with your local dealer service department to find out what Porsche recommends for your car.

The service interval for plugs may be tied to the VIN so do not assume it will be the same as another person's car.

For a tuned car or a car fitted with aftermarket hop up parts, the company offering the tune or aftermarket hop up parts should have a spark plug change interval recommendation, maybe even recommend/advise you use another/different plug.

 

Im using 15-20k max plug intervals. Stock cars can probably go 30-40k easy enough.

 

Even Porsche isn't consistent in their published interval - 2007 TT change plugs at 40,000 or every 4 years / 2008 TT change plugs at 24,000 or every 4 years / 2009 TT change plugs at 30,000 or every 4 years. I don't believe the engine changed from 07 to 09 - same GT1 based Mezger engine. Go figure.

 

If I recall there was a change in intervals, from 40k to less and it was for all 997.1 turbos.

 

Maybe...but the pages I attached show 3 different intervals for the 997.1 turbo.

 

Thanks - hence the confusion! Rep points to you! Sounds like a 40k interval for a stock car is reasonable. That chart is really messed up, the 997.1 turbo first model year was 2007, yet they list the service interval for the 2005-2007 turbo. Not sure if it was out in Europe in '05, possible I guess. But then I don't think there were ANY engine changes from '07-09. Really weird.

 

Lol I called dealer just to get a quote to change spark plugs, they told me $1500 and I was start laughing....

 

When it needs them. I got 50k my car still runs fine. No hesitation, mis fire, nothing.

 

You can have trashed plugs with no misfires, no hesitation, no CELs...you think everything is fine, but it will rob you of power as the computer tries to compensate for a crappy spark.

 

What do you recommend?