2004 Saab 9-5 2004 Saab 9-5 - Turbo inconsistent

2004 SAAB 9-5
150,000 MILES • 4 CYL • FWD • AUTOMATIC
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JIMMMMINY
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  • 1 POST
Occasionally, when I am driving on the highway, the turbo will sort of rev up and down on its own rather than being applied smoothly/consistently. This typically happens when I am applying consistent pressure to the gas pedal and the engine is under medium load - for example, going up a gradual hill at a consistent speed (~65 mph). This does not happen all the time, but when it does happen, it usually occurs throughout the duration of a particular trip. Then, if I turn off the car, let it rest/cool and start again, it usually does not reoccur for several days/weeks.

Any idea what this could be or if it's anything I need to worry about? The car otherwise runs fine and has never had any major repairs.

Thanks
Aug 18, 2010 at 4:08 PM
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MNTHNY4
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  • 612 POSTS
hey what's up, just a question is this car a AERO model ,reason been the only car that i had worked on for the same issue u r asking about was a aero ,what had fix the issue was the replacement of the trionic control module .that is the main engine computor [ECM],note did u check all your small vacuum type hoses from turbo pressure valve & turbo bypass valve ,note bypass valve at front with long thin vacuum hose running to pressure valve mounted to firewall also get both valve vacuum checked if they hold a vacuum ,but anyways turbo gauge to controled by the ECM .GOOD LUCK .
Aug 19, 2010 at 2:21 PM