Misfires?

I am looking to collect some info on misfires on Cayman S 's. I have just had my warranty claim refused by Porsche because they say my Milltek exhaust caused the misfire. I am wondering how many owners have had misfires, but mainly on zero modded cars? The cat on the r/h bank of the engine was melted I am told and this was the cause of the misfire. I wonder if the misfire came 1st then that trashed the cat, which means it probably happen again, even now I've got the original exhaust back on. I got the engine log print out and there was 14 misfires from cylinder 3, one or two misfires on other cylinders. Any info will be of great use, even for my own peace of mind as I'm pretty sure Porsche GB won't change their mind.

Sorry to hear about your problems. I had misfires on all the cylinders on the right side (1,3,5) when the car only had 700 miles on the clock. It have been sitting for 10 days with 1/2 a tank of gas in cold temps (-4 tp -7 degress C). After warming up and driving 10 or so miles, the car sputtered and the CE light came on. After filling up and restarting, the problem went away. The dealer pulled the spark plugs to check for fouling and found no issues. I'm at 3200 miles now and haven't seen it happen again <<knock on wood>>. I always top the tank off after driving it now (easy to do since I only use it once a week at most).

It might be a good idea to start a list. My car had misfires when the Milltek cats failed, which occurred first I don't know, but after replacing the Milltek cats the misfires went away. Scott Slauson the PCA-TECH told me there was a Porsche service bulletin on misfires for the Cayman but I'm not sure we have it in our library so you might check with him and see if he has it. What is it you are asking Porsche to cover? They won't cover your Milltek cats, was something else damaged? I know of at least one engine replacement where there was some cam bolt that was the wrong size and that the engine had misfires and was replaced by Porsche but I don't know if those misfires were related to the missfire service bulletin or not, again ask Scott he probably knows the details. Obviously continue to monitor your car for misfires.

Hi there i am up in Aberdeen too, I was just told by official porsche (town and county) where i bought the car that any mod too any part of the vehicle, would invalidate the whole warrenty. Why is UK Porsche different to usa porsche? Anyway good luck in trying to get a result. Did they give you an indication as too the cost of repair. James

I know they won't cover the Milltek cats, but I would have liked say that there is a history of misfires with the engines and would they swallow the cost of labour for checking the vehicle. As for the Milltek cats, that's money down the drain as Milltek no longer manufacture them and also don't honour the warranty on them. They say the issue is with Porsche and their merchandise is perfectly acceptable. I will keep checking for misfires, just incase. The bill is still being totalled, it was 10 hrs labour, might be more now....

Has anyone seen a gas-pump icon in their computer display associated with this problem? This is not the gas-pump icon followed by the arrow which indicates how much gas you have left. This icon shows up on the line above, where the radio information cycles between the station and the song. I started seeing this icon, preceded by a number, such 1 and 3 before the Check Engine light came on. When I took it in, Porsche found "...faults for coils, swapped coils and verified connection." I saw the pump icon preceded by the number 1 as I drove home from the shop, but no check engine light. The Porsche guys say they've never heard of this icon. I checked the owner's manual but no such icon is listed. Are any details available with regard to that service bulletin (an ID of some kind)? Thanks!

When I first bought my car it had misfires too. stock exhaust, stock software. I know it was 3 cylinders. since I have modded the car the misfires came back once but that's it. All I know is that P0126 code is around which is some "limit stuck" code that cant be cleared. Maybe thats related? Did you have a P0126 code?

In my experience they are not, but it very much depends on the relationship you have with your dealer, both Chester and Bolton have told me that if you have a warranty claim related to some none Porsche part, thats your problem (i.e. fit a quaife diff and you diff blows ....tough) but if you have trunk clunk 3rd brake light rattle they will fix it ...under warranty.....well my cars a just a little modified and I've never had an issue with the local OPC sorting it. They have been very good in fact. (Just on my way NOW to look/sit in the new CaymanS-2 with PDK etc,etc.)

Never a misfire on a non-modded CS. (OK, I did the clear side markers, so sue me!)

My car went over 2 years without mods, not a single misfire. Installed FabSpeed headers and cat back. After 2 track sessions, exhaust note sounded different and within days the car was misfiring. Headers were removed revealing fractured catalyst media. OEM headers were put back on along with the FabSpeed cat-back. No subsequent misfires even with several track sessions.

Stock 2008 CS had misfires on cylinders 1 and 3, car had been sitting 2 weeks with 1/2 tank of gas. Refilling with new gas and driving a few miles the CEL went away.

I had the same thing happen to my 2008 back in the winter of 2007/2008. A fresh tank of gas and more than 13,000 miles later, no further issues..

I had a misfire early on once when the car had been sitting a while. It ran rough after starting then threw a CEL. Not sure if the code cleared itself or I had to go to the dealer, I think the latter. Completely stock.

I had misfire this winter and find out that two of my ignition coils was cracked /the plastic cover / ,change all the coils solve the problem .I'm driving 2006 CS.