current47

Hey everyone. Still newbie to these forums so any words of wisdom would be most appreciated. I just got a new 997S around 4 months ago. I have been extremely careful in the breaking in period. I observed the 4000 rev limit as suggested for the first 1000 or so miles, but after 1500 I was moving around all rpm's (nothin crazy/max 5000) engine breaking hitting the full spectrum on revs all around as suggested by many kind posters...

Earlier, under 500 miles, I experienced some jerking in the throttle (ie uneven acceleration when slight gas applied). I posted this on one site and it was suggested that it could be bad fuel or not warming up the engine. No issues through 2200 miles.

Earlier today, took a 300 mile drive and the last 50 I experienced the jerky throttle once again. I had a half tank of fuel and put some fuel injector cleaner w/ a top up of 93 Amoco gas and still had the jumpy throttle. It felt like the fuel line was getting choked or something but what do I know...

Any suggestions???

wilam

I have the same issue and it is more pronunced in the "sport mode" and funny enough it is especially worse when I use a 50% blend of 100 Octane Shell racing fuel mixed with 91 Octane fuel.

gpjli2

Had one incident in 6500 miles the only time I used Sunoco. Never w Shell. Coincidence?

Tony356993

Search the forum for "throttle body" and you'll get some info. Here is my post after I experienced the same problem. Do you have an '06 or an '07?

I now have not had a problem after the dealer performed this fix. Goodluck.

Holli82

I get it every once in awhile. I am still unsure as to why. I get it after I fill up, I get it when I'm almost empty I recently got it at 1/2 tank. I get it with sport mode on/off. I get it with different brands of gasoline. Usually will go away after the car sits for awhile.

I took it to my dealer and of course it ran just fine. It is more frustrating than chasing a rattle in the dash.

I wonder if 91 Octane ( the highest we can get out here) is responsible?

current47

Its a 2006 C2S.

Tony356993

Ask the dealer to perform the throttle body adjustment. They will be paid by Porsche and it cannot hurt.

500

Sounds like it could be related to the hesitation issue that's been actively discussed in this forum; here's two threads of many:
https://rennlist.com/forums/997-forum/277930-my-car-acted-up-big-time-hesitating-and-very-jerky.html

https://rennlist.com/forums/showthre...ght=hesitation

Holli82

thanks for the link. I must say I've reviewed all of the links on the 997 forum and on other sites as well. Bottom line is there is no one clearly defined easily reproduceable set of factors that I've been able to determine is the cause. More importantly, there is no well defined "fix" regardless of the cause. Maybe the throttle body fix is it.

500

Had a similar problem with my 06 E55, the car threw no codes at all. The car was then thoroughly diagnosed by the local dealer and with the MB rep present; the car was given a clean bill of health and I was told I wouldn't have the problem again. Within a month of leaving the service dept the car stuttered/bucked and hesitated almost causing an accident and I did not refuel that day or even that week. The problem was finally diagnosed as a loose wire to the fuel pump and MB admitted it was appearing more and more and quite embarrsasing. BTW, the only way they found the cause was it finally died on the interstate and would not restart and the delaership was able to trace the problem.