997 acceleration
#1
Racer
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997 acceleration
I have a base 997, and I've noticed a "flat spot" between 4800 - 5000 rpm's when I'm accelerating hard. This is the first 911 I've owned and I'm not sure if this is normal or something that I should be concerned about. Has anyone else noticed this? Btw It's most noticeable between 2nd and 3rd gear. Any feedback would be greatly appreciated!!
#5
Very good catch. I notice something similar. I was planning to put it on the forum, but didn't came to it, yet.
Sometimes I have the impression that the fly by wire mapping isn't flawless. Picture the situation that I'm accelerating starting around 2000 rpm and around 4500 rp I'm starting to back off. When close to no acceleration anymore, I sometimes feels a last additional little unexpected push, as if the controller to the fuel valve is making a last little move to its final position while my foot was already steady for a second or two. Also during fast acceleration I sometimes have the feeling that the fuel system is changing its mapping behavior, such that you feel a short change in the acceleration curve (indeed around 3000 - 3500 rpm).
I have to say that I can't put my finger on it, whether it is consistent or just imagination, but it happened already more than once.
Sometimes I have the impression that the fly by wire mapping isn't flawless. Picture the situation that I'm accelerating starting around 2000 rpm and around 4500 rp I'm starting to back off. When close to no acceleration anymore, I sometimes feels a last additional little unexpected push, as if the controller to the fuel valve is making a last little move to its final position while my foot was already steady for a second or two. Also during fast acceleration I sometimes have the feeling that the fuel system is changing its mapping behavior, such that you feel a short change in the acceleration curve (indeed around 3000 - 3500 rpm).
I have to say that I can't put my finger on it, whether it is consistent or just imagination, but it happened already more than once.
Last edited by PV; 05-03-2005 at 12:33 PM.
#6
Rennlist Member
No, but a couple guys here (me included) noticed that if you accelerate slowly, at around 3600RPM there is a little "burp" for 200 RPM or so. If you are hard on the throttle it doesn't seem to be there..
Or maybe it's around 3200...
Or maybe it's around 3200...
Last edited by Gary R.; 05-03-2005 at 12:54 PM.
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#14
Racer
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So I guess I'm not the only one. I brought my car in for service today to fix the system fault hood latch problem, and decided not to mention this acceleration concern until I was able to check back and see if anyone else had experienced it. Knowing the service department at my dealership it almost seems like a waste of time to have them check it, the ansewer will be "we didn't notice anything". What are you guy's planning to do about this problem?