9-5 runs rough

[TKranda]

Hello again,

I have had my first Saab, (9-5, Aero, 2004, 25K miles) for a couple of months now.

It has always run rough in idle and smooth, very smooth, when underway.

I have replaced "damaged or worn" motor mounts and the ignition coil(?) which apparently had a code indicating "1 of 4 cylinders misfiring." (That seemed odd as there was plenty of smooth power). And the plugs of course (tripple checked and am confident I have the correct plugs).

Anyway, she is still noticably and somwhat embarrassingly rough when stopped (stearing wheel vibrations, no noise).

Is this a normal trait for the 9-5? Or will I be chasing this phantom forever?

Any advise or help is very welcome and would be much appreciated.

Tom
Phoenix

[nordwulf]

This is common for the 4-cylinder and automatic transmissions. My 2001 was pretty bad with vibrations in the steering wheel. There is a TSB about this issue and has to do with the idle speed.


TECHNICAL SERVICE BULLETIN
Bulletin Nbr: 248-2565
Date:...........Juni 2005
Market: US/CA

Vibration at idling speed

Cars affected
Saab 9-5 M98- with engine alternative B205, B235 and B308

Background
In certain vehicles, the vehicle may vibrate when it is stationary.
Vehicles equipped with automatic transmission may have the idle speed set higher than the
typical idle speed. While the vehicle is in this condition, the driver may experience abrupt
shifts as the shift lever is moved from park to drive or reverse.

Symptom description
Vibration in the body while stationary. Abrupt shifts as the shift lever is moved from park to
drive or reverse.

Procedure
1. Establish whether the car has idling speed vibration problems or shifts abruptly.
2. Adjust the engine's idling speed. Connect Tech2.
• • • • • • •
If the car exhibits vibration problems during cold starting for example, then the speed should be increased at a minimum (10 - 30 rpm). If the problem remains at all engine temperatures, then increase the speed by more than 30 rpm.
If the vehicle shifts too abruptly when engaging gear, lower the engine speed in steps of 20 rpm.
If the car is equipped with automatic transmission then the customer should be informed that the tendency to shift abruptly will increase if idling speed is increased.