To check your fuel injectors get a clear container (a coke bottle works just fine).
Take caution as you are working with fuel.

1. Take one injector out of the car at a time starting at #1 and put the injector it the bottle so you can see the spray.

2. Turn the key to the on position to allow the fuel pump to run and observe the spray pattern of the injector.

If it does not look like an even spray, exchange another fuel line for the one that just tested bad. If after replacing the line the spray is still not good swap the bad injector onto another line. If the spray is still not acceptable, replace the injector.

a. if the spray becomes acceptable when replacing the line - you have a plugged line

b. if the spray becomes acceptable when relocating the injector onto another line - check the fuel distributor

c. if the spray after relocating both the line and the injector is still poor - check the fuel system

Remember - replace those fuel filters. YES! BOTH! One in the engine compartment, and for 1977.5 and later Porsche's one right near the gas tank. Replacing with new filters will make a huge difference in performance.

The fuel injectors plug from use because of a filter that is located in the injectors. You can get it renewed at some shops that have the machine to pressure spray the injector (they spray it backwards from the normal way the fuel goes through). It costs about $10 to do. You can get new injectors for about $30. A cleaned injector is as good as a new.