Thanks - you have no idea... came very close to throwing in the towel on this one. Was one thing after another!

 

Hadn't considered excess back pressure from malfunctioning/stuck VTG vanes. Excessive Back pressure is a real no no on a turbo and will cause abnormal combustion...no question. That in itself brings about a whole nasty range of scenarios none of which are too kind on the piston crowns, rings, exh valves, seats and guides. The extent usually depends on time, distance and operating conditions during that period. The fact the plugs gave way so quickly is testimony that you had some nasty temps going on in the cylinders unfortunately. Only a full strip down will determine the real consequences but if the engine is running fine then best leave sleeping dogs lie. GL.

 

I think it's the tune, or more so what the tune is indirectly causing to happen. It happened on two of my cars, both 996's. I went through two sets of plugs on both in little time, very frustrating and expensive... The only car that didn't do it was the Ruf 550 tune. Over the years I've always found it strange that the "tuners" never do get involved in these threads when they come up. I think in the "under world" it is very common knowledge these tunes chew plugs. I did get Stephen at Imagine to admit it was a problem at one point. I was in his shop when there were three different modded cars there for plug jobs and i confronted him. Boy, they'll buck like crazy, throw CEL's, and even can go into limp mode when they foul, very scary

I'm pretty much done with tuning until I'm convinced this issue has been resolved. The fact this thread is revealing the opposite, coupled with the fact no tuners have jumped on to defend the issue, pretty much tells me it hasn't been resolved...

 

It appears that in the OP's case, it was mostly mechanically related rather than the tune itself. The higher performance of the tune may have exacerbated the problem. With these high performance tunes, everything has to be working correctly otherwise it could be bad. I also would never trust pump gas when going full out even if the tune was "designed" for it. That is risking it, imo. I think Porsche got it right to set the lower performance on stock simply because of the variability in fuel quality across the board.

 

Yep, exactly... Albeit I was actually running 101 one of the times it happened but who knows if it really was truly/purely 101... I've just heard of so many people fouling plugs over the years with the 911TT's. I wonder if the GTR's are fouling at the same rate the Porsche's are? I haven't heard of any of them at this point fouling however, as mentioned earlier, it seems taboo to talk about among the masses, kinda like a prostate infection

 

Sharky talked about the plug issue in a previous thread but unfortunately it looks like the pictures are no longer there.

https://www.6speedonline.com/forums/...97-turbos.html

 

I agree Porsche has provided a sound tune platform which provides durability and longevity in all operating conditions so long as the specified fuel is used and the engine is also being correctly serviced. Herein lies the problem with AM tunes. Everything really needs to be working 101% particularly during wot operating conditions. What needs to be established here is the the cause and effect behind the seizure of the vane adjustment rods. We know these rods run in guides and there is lubrication required to ensure free operation/movement. Normal heat diminishes lubricational properties over time hence the need for oil changes and the likes (lubing of adjustment rods included). Excessive heat burns lubrication away totally (and very very fast) and then the environment exists for (rod/shaft to guide) seizure. Once the rods begin to lose their normal free movement the problem then rapidly accelerates and shafts will then seize. We all know AM tunes must produce higher combustion temps. They have to. More boost combined with more fuel = higher combustion temps....it's that simple. It's compensating for that excess heat that becomes the real issue here. More efficient intercoolers and a higher flowing exhaust are essential if you intend using any tune during wot driving. If you can't control your IAT's and exhaust gas temperatures the turbo housings are going to heat up much more. The scenario then becomes like a forever decreasing circle. Some tunes control the timing and detonation better than others. Some remove certain safety measures too. Dave I agree using premium high octane fuel is a preventative measure but it is unfortunately not a panacea. I personally think a set of IC's and a decent system are required to give any tuned engine a fighting chance....along with a data log of the tunes behaviour under harsh wot conditions.

 

How long should stock plugs last on a bone stock 997 turbo fed 93 it's whole life

 

100% stock turbo should change 30-40K- Plugs tend to fail sometimes so it never hurts to change early- I have 29k and had the plugs swapped 4 times. The spark plug change/ upgraded coil pack is a good option to upgrade to; relatively easy for a good tech as well-

 

What is the benefit of the coil pack change?