My brand new 997S Cab experienced abnormal jerking at around Mountain High. It jerks when I throttled it. Once we got down to lower altitude (like fwy 15) and the jerking was gone. During the occurrence there were no any warning light on and the engine sounded fine. Prior to the Mountain High the car ran fine from fwy 210 to hwy 2. Could this be the oxygen sensor’s malfunction? Or, Porsche did not program the oxygen and fuel mixer at such high alt? By the way, before we headed up the mountain I topped the ¼ filled tank with 76 gas. When we reached the low alt we topped the 1/3 filled tank with Shell. Would the gasoline played key role in this case? Appreciated if you have any answer!!

 

SOUNDS EXACTLY LIKE MY CAR. sAME THING HAPPENED TO ME BUT I WAS NOT IN HIGH ALTITUDE. DEALER NEVER DIAGNOSED THE PROBLEM AS IT MAGICALLY DISAPEARED. NO CHECK ENGINE LIGHT EITHER. HOWEVER, 2 MONTHS LATER THE CHECK ENGINE LIGHT POPPED UP AND THE ENGINE COMPLETELY HAD A **** FIT. IT WAS JERKING HARD AND COULD BARELY STAY ON. SMOKE WAS ALL OVER THE PLACE AND THE CAR WAS VIBRATING AND JERKING MASSIVELY. OBVIOUSLY, HAD IT TOWED TO THE DEALER AND AFTER A WEEK OR SO, THEY FIXED THE PROBLEM. SAID IT WAS A SOLENOID SOMETHING OR OTHER. IF YOU NOTICE MY AFFILIATION WITH LEMONS, YOU NOW KNOW WHY. GOOD LUCK.

 

Thanks Judge! I hope mine won't be the case....... Well, I am waiting the snow to melt and go back up again to see the issue still exist. I'll keep you guys update!!

 

I had the same thing happen, 997S with X51. One morning the car felt like it was running on 3 cylinders. No CEL. It returned to normal on its own. Dealer found nothing wrong. He did say this is the 2nd car that experianced this.

 

Same here. It did it 3 times so far. The dealer found nothing wrong.

Judge, can you scan your invoice so we can see the diagnosis?

p.s. my car fixes itself without warning. I have no idea why it does that, but it seems to run on fewer cylinders.

 

This is very odd........ CAN WE DO SOMETHING ABOT IT?!?! I DON'T WANT ENDED UP LIKE JUDGE'S LEMON!!! I'VE READ HIS STORIES......