2005 Cayenne Turbo Cylinder 4 Misfire

[RacerX5]

Another "non-invasive" diagnostic test you could try would be a combustion leak test. This can test for a blown head gasket, (keep in mind there are times when a head gasket can fail with no white smoke, and only very tiny coolant loss).

The tester looks like this:

http://store.snapon.com/Leak-Testers-Tester-Combustion-Leak-P642924.aspx

At $85 for one of these testers, it would be good information. Basically, fill a compartment in the turkey baster thing with a special fluid. Then suck in some coolant. If combustion gasses are present in the coolant, the fluid changes color.

[olliedad]

Hello guys. I have a 2005 Cayenne Turbo (actually my wife) with 105k miles. We noticed a small misfire, and per the sound coming off the motor I thought it was a hose loosing air or compression. Took it to Porsche and on cylinder #2 we were only getting 40 PSI compression (pretty much nothing). Good we had an extended warranty... turns out that one piston had literally a whole. We were told that it had caused by the use of poor quality gas and the use of additives to compensate. The mount of ethanol caused the pistons to burn and eventually one of them to fail. As I said, thank goodness we had an extended warranty. I have several photos in case you need to look at them... so, no more use of additives.

Edited April 12, 2014 by olliedad