Porsche Repair: 79 928 car starts but no rev HELP, air fuel ratio, air flow meter

Question
I can start my car but it wont rev up when I step on the gas pedal it has new warm up regulator,wires,distcap,coil,battery,fuses,relys, green wire,gas filter,two fuel pumps working well,the owner before me changed timing belt and water pump.The car ran well until i got cougt in a rain storm. HELP Thank you Peter

Answer
Hi Peter,

I'm going to assume the rain storm is a coincidence.  Your symptom usually occurs when there is a vacuum line broken or disconnected.  A vibration or inadvertent elbow is often the real cause of the defect.

If the vaccum lines are OK, then the next bet is the idea of "false air".  False air enters the intake manifold surreptiously...meaning air is being sucked into the combustion chambers via the intake manifold withou having been "measured" by the airflow meter.  This resuits in a poor air/fuel ratio.

The flow area to be concerned with is: after the air flow meter and before or at the intake manifold.  It's similar in nature to a vaccuum leak but instead of a broken hose, it's a leak at a sealing surface.

Dave