Ajjra

My 987.1 feels a little rough on deceleration between 2,000-2,300 rpms. Any thoughts on what it could be? Feels like bad pavement (not that bad but best reference I could come up with)

Thanks in advance for any help.

cvazquez

What happens if you deceleration in neutral gear to a complete stop or cruising speed.

Ajjra

Nothing in neutral. I notice it most in 2nd gear.

Macster

If if only happens in gear and with no other abnormal behavior my WAG is the car has some drivetrain/tire/road surface harmonics that accounts for this.

My Boxster can manifest a noticable though not severe vibration when coasting down on closed throttle through the 3K rpm region.

Intake resonance flap changing coupled with harmonics. The car has done this over 250K miles.

Because the car is so smooth -- like driving a sewing machine one guy who drove/road in the car told me -- that the vibration while mild still makes me notice it when it happens.

Surprisingly the behavior is often more pronounced on smooth pavement.

Couple of things to consider. Tires may need air or you may have too much air in them. Tires can go out of balance as they wear and a mild tire/wheel vibration may be the cause. The techs tell me the bigger diameter the tire, or the wider the tire, the more likely this is to happen.

Tires make more noise at they wear and age (experience an every growing number of heat cycles).

Alignment: Word is many (around half in one article i read about this) cars that visit a dealer have incorrect alignment. The car may have not had a good one to begin with or over time as things have settled the alignment may have gone out.

Up to you how much time and money you throw at this behavior.

'course I haven't experienced the behavior so just to be safe you might want to have a Porsche tech test drive the car with you along side or ride along as you drive the car and demo the behavior.

I do not think it is serious, but I'm not a trained professional tech.

Sincerely,

Macster.

Ajjra

Tire pressure and alignment are good, but the intake is not something I had considered.