2007 S80 3.2 Hesitation/falt-spot trouble

lupo · Post by **lupo** » 12 Mar 2007, 00:03

Hi
I have a brand new 2007 S80 3.2l and I have the following problem.
WHen I am in six, in auto mode, and I need to pass a car and accelerate, the car changes to fifth and at exactly 6000rpm it has a flat-spot..When on a hill, its really bad and it jerks for a while before changing at 6 500 rpm. The same thing happens in manual mode at 4000rpm in any gear under full acceleration.

The car has been on Vida and displays no error codes. Can anybody assist with this one as I am lost for words. This is a brand new car.

Thanks
Regards
Mike!
South Africa

petershen1984 · Post by **petershen1984** » 29 Apr 2007, 14:56

Pardon me, but if you stop at red lights in intersections, have you noticed bars of the same color where your tachometer indicator has been regularly visiting?

The flat spot you describe is because your car has a low torque peak at around 3,300 rpms. Naturally aspirated cars have trouble breathing (making power) beyond torque curve, and it will drop drastically now that you're in the peak rpm before the red lines.

That is why you have a six speed gear box. To make use of the narrow peak efficiency range, six times.

And further, if the engine ventures into the red line, the computer will trigger fuel interruption until the engine speed falls below the danger level. This is why if you've seen race cars rev their engine in neutral, they seem to accelerate to max rpm and surge, and then go back up again like an absolute sine wave (alternating current, rectified).

Love your Volvo, by all means. don't abuse it!

You are doing damage that your new car may not be ready for. It's like extensive weight training on your first day at the gym.

Peter

damotu · Post by **damotu** » 04 May 2007, 10:36

I believe 'Lupo' was inquiring about 'Flat Spots' upon acceleration and quite frankly he should have "None" until he reaches peak RPM and only then...If in fact hesitation occurs within any gear (up to peak rpm) then the vehicle should be returned to the dealer...
If it were my car, it would stay with the dealer until this problem no longer exists...
Your not going to damage the engine by going fast and keeping within the peak rpm range in all gear selections...If you do exceed this peak range then yes, the engine will shut down, thats what the computer is for, thus avoiding engine problems...
Take it back to the dealer and tell them to fix it...These Volvos are on the upper up in price, so there should be very little faults...Good luck