Question87 alfa spider-the vehicle sarts no problem and engine will accelerate evenly if the gas is depressed slowly except it will stumble at 2500 rpm. A rapid acceleration will cause the engine to stumble at any rpm. The fuel system has been completely rebuilt and pressure tested. The computers have been checked and are OK. Cold start valve is OK. Airflow meter is OK. RPM sensors check out. Air start valve OK. injectors replaced 12 months ago. Thermal valve ok.
Answerone step at a time. First: all too often the fuel pressure
is checked but, not the volume the pump produces (at least
a pint in 20 seconds). Also, if idle is too high then an
air leak is indicated. After checking fuel pump volume, also
look at the spark plugs and tell me the color of the
electrode and the gap of the plug.
