CLICKING NOISE DISAPPEARS WHEN PRESSING BRAKES

A loud clicking noise that sounds like it is coming from the radiator area is caused by a switch that is located above the clutch pedal inside the car. This switch is called an Turbo pressure switch. It is a safety switch designed to prevent engine damage. The noise in the engine compartment is created by the APC solenoid which is located just above and to the right of the Radiator. The correct repair is to replace the Over pressure switch.

Thanks to Keith Mehnert for contributing to this FAQ!

Fyi, the manual tells you to tear the dash apart for this change out, don't go there, just remove the seat and lay a blanket for over the seat tracks and lay down look up. You may have to peel back the black vent behind the knee bolster and put it behind the brake pedal. You just needed to remove one screw for the plastic heater difuser and bend out of way which will not hurt anything. Using a Flashlight is helpful when changing this out. Hope this helps. I am a 30 yr saab owner, 3 of them 84 4dr turbo, 92 3dr, and my baby 88 turbo convertible, and I have never had any one else work on my girls.