White smoke and rough idle -used to take 10 seconds, now much worst.

[Audax]

I'm pretty certain it's sent to the instrument unit from the coolant temp sensor reading in the engine ECU, I'd be looking at cleaning all the intake air temp and MAF sensor and testing them properly.

[sgould]

There is only one coolant temp sensor.  There is also an outside air temp sensor in the front lower grille.

There's an intake air temp sensor in the manifold, which also measures air pressure.  As I understand it, this compares the temperatures with the outside air temperature and adjusts  the fuelling to suit.  But modern diesel engines are a bit beyond my experience.

https://saabwisonline.com/9-3-9440/2008/2-engine/4-cylinder-diesel/intake-system/technical-data/intake-air-sensor-688-edc16

[dave08]

I'm pretty certain it's sent to the instrument unit from the coolant temp sensor reading in the engine ECU, I'd be looking at cleaning all the intake air temp and MAF sensor and testing them properly.

Thanks! I've clean them already and checked some values with opcom, but that doesn't mean they are working properly. As for the coolant temp. sensor, thanks. I could not find any other info in WIS (except for dual sensors in cars for nordic market with aux. pre heater).

[dave08]

There is only one coolant temp sensor.  There is also an outside air temp sensor in the front lower grille.

There's an intake air temp sensor in the manifold, which also measures air pressure.  As I understand it, this compares the temperatures with the outside air temperature and adjusts  the fuelling to suit.  But modern diesel engines are a bit beyond my experience.

https://saabwisonline.com/9-3-9440/2008/2-engine/4-cylinder-diesel/intake-system/technical-data/intake-air-sensor-688-edc16

Thanks! I replaced the MAP sensor 4 years ago. Although it solved an intermittent sluggish/jumpy acceleration the smoke was still there.

[Steve McF]

One of the guys should be along soon.

I'm not up on the diesel at all, I'm afraid - mine's a 2.0T Aero!!!!