jlenze

Hi Guys

My C2 has difficulty starting at times. Put in a new fuel pump relay and still it cranks for about 8 seconds then catches. Car runs beautifully otherwise. This is not specific to hot or cold engine. Any suggestions.

TIA Jack

TMc993

Sounds like the check valve in the fuel pump may have gone bad. The check valve holds fuel pressure in the system when the engine is not running. The pump works, but when you turn the engine off, the faulty check valve allows fuel pressure to leak down. Then, the next time you start the engine, the pump has to run for a few seconds to build up enough fuel pressure to enable the engine to start.

mr_bock

Fuel filter? Fuel pressure? Old fuel?

Vandit

If your fuel pressure regulator is failing, it'll bleed off pressure when the car is parked, thus creating a hard start the next time you turn on the car. Find the vacuum line for the fuel pressure regulator. Once the car is running, disconnect this hose and watch for fuel to burp out of the vacuum line fitting. You don't have to disconnect the line at the FPR, but instead where it connects at the intake manifold. Maybe someone can point it out on the 993, cause I only know it on the 964.


Basically like this (generic non-Porsche video).