Limited performance SAAB 9-3 1.9 Victor sport TDI

I can't see it myself even though I have no experience of the car model.

Lots of the vehicle content is Vauxhall/Opel/GM (I think) suitably modified by Saab.
It doesn't sound logical that a dodgy cruise control switch would cause reduced performance. A reduced performance condition is usually caused by something that affects tailpipe emissions or something affecting engine integrity or reliability.

I heard on the grapevine some Vauxhall models have reduced performance simply because they are overdue for some maintenance and once the service indicator has been reset they are fine again. I don't know how true this is. I know of one Vauxhall that flags up an overboost fault and cuts performance when there is an egr valve fault. The true cause could not be discovered by a generic obd scanner and it was only when it was plugged into something with some very expensive dedicated software that it became obvious.

There is no telling what the Saab boffins have done to the management programmes. There are vehicles around that go into reduced performance if the oil level or pressure is low and maybe they thought that might be a good idea.

I suggest you continue your Saab research at the local Saab dealer or on one of the specialised forums, but certainly I suggest you get the code re-read by a dedicated diagnostic machine.

Perform a diagnostic before doing anything on this type of vehicle it may save you some money in the long run

limited performance indicates that the ecm put the engine in the low power mode due to a problem encountered with a sensor ( low oil level-pressure, overheat /low coolant level, gear box temperature over heat, loose position sensor/s . Run the fault codes first to determine where the faults are. Check that the cam shaft is turning ( broken timing belt)

try the idle control valve it could be starting to fail.

the gearbox goes in limp mode if it detects any problem with either transmission or engine, if you have misfire in thengine,the transmission module might put it in limp home mode,have your car scanned for issues.

Is it stick shift? or automatic? If it's manual it's one of the gears is gone bad, no amount of oil changes will fix that.

Hi you really need to get the trouble codes read out the engine ecu but from experience the most likely cause is the EGR valve or throttle body.

Hope this helps

John

If you have a 4 cylinder check out this sight for a diagram of serpentine belt http://www.thesaabsite.com/93/93pulleys.htm#BELT+%26+PULLEY+SETUP+%28NOT+SPORT+SEDAN%29

Call a SAAB Dealer

check EGR,MAF,injectors,high pressure sensor(fuel)