Misfires?

[mikec]

I've just had an issue with my Boxster Coupe, it had a misfire/judder and the engine warning light came on, I couldn't stop immediately so carried on the road, slowed down and looked for a safe place to stop, the car juddered and the light continued to flash, then the light went out and the warning disappeared. After investigation by Porsche Aberdeen, where at 1st they found a solenoid wrong with the vario-cam, they found that the CAT on the r/h side of the engine was melted. I did have a Milltek 200 cell full system fitted, after they re-fitted the original system they now say the misfire is no longer. I find it hard to believe, I did get the engine log print out and it shows 14 misfires on cylinder 3 after it was in the workshop. What I want to know is if anyone has had a misfire issue and if so has it been resolved properly by Porsche? I wonder if the misfire came 1st, thereby flooding unburnt fuel in the CAT, then the unburnt fuel ignites it burns the CAT out as the tempature is way above the normal operating range of the CATS.
I wonder how many Boxster owners have had this problem, if at all, I'm asking on the Cayman forum too.

 

[Black80XSA]

most misfires are down to faulty coil packs - i doubt one would fail yet ona Cayman, normally 4 years or more, but any extra heat in the area from a differently routed exhaust might not help. Coil packs normally only become problematic in damp conditions though- they can run fine with lots of heat cracks in them in dry conditions.

 

[StephenWicks]

Sounds similar to my recent experience on The Boxster Tour of Scotland[8|]

http://www.porscheclubgbforum.com/tm.asp?m=374817

 

[mikec]

Yes it does and the engine log file showed 14 misfires on cylinder 3.... There was misfires on cylinder 2 also but 3 seems to be the main culprit. Any other takers. As for the exhaust, I would say it's as close to original as possible, any extra heat would have been from the fuel igniting in the CAT. The Milltek can use either Porsche's own CAT and it's rear section. or Milltek CAT's and Porsche's own rear section. It is a good system, the CAT's are purchased from HJS Motorsport in Germany, which make FIA approved CAT's for motorsport. I do wonder if the misfires came 1st. Remember VAG a few years ago when their coil packs would fail willy nilly, I had 2 fail on my TT at the same time. It was only 4 months old.