As the hood insulation on 944 ages it will flake off and make a mess all over the engine compartment which is extremely difficult to clean up. The solution to this problem is to remove the old hood insulation. After the hood insulation is removed, you can replace it with new insulation or you can simply leave the insulation off. On late model 944s, Porsche did not install hood insulation.
3M Woodgrain and Trim Remover
Soft blanket, large rug, or large soft piece of carpet (to lay hood on while removing insulation)
First, remove the hood from the vehicle as follows. You'll need and assistant to help you with this.
Disconnect all of the hoses for the windshield washer nozzles. You'll also need to disconnect to disconnect the wires for the washer nozzle heaters.
Disconnect and remove the hood shocks.
Prop up the hood. You can buy a professional hood prop at many auto parts store. However, a broom stick cut to proper length works almost as well.
Finish removing the hood by loosening and removing the bolts that attach the hood to the hinges (two bolts per side).
Have an assistant help you lift the hood off of the car and lay it upside down on a blanket.
Using your hand or a plastic scraper, remove as much of the old hood insulation as possible. What should remain is primarily the adhesive used to attach the hood insulation.
Apply the 3M Woodgrain and Trim Remover to the hood insulation adhesive and allow it to sit for approximately 5 minutes.
Using a soft cloth, to gently rub away the softened adhesive. DO NOT USE any type of scraper after applying the trim remover. Sometimes the trim remover will soften the paint. If you use any type of scraper, you chance damaging the paint underneath.
Once all the adhesive is removed, wash the area thoroughly, dry, and apply a coat of wax to the underside of the hood.