Re: Volvo Penta 5.7 gi fuel pump relay
So you bypassed the fuel pump relay?
You may have overlooked Bruceb58's question earlier. Did you happen to try running the engine over 3000 rpm with the relay jumped as well?
Bear in mind that highlighted below mentions an overheat may shut down the engine.
MEFI-4 Inputs
CS - Crank Sensor (a.k.a. Crank Trigger) ? crank angle (i.e. where each cylinder is in its 4-stroke cycle) & RPM.
CTS ? Coolant Temperature Sensor - engine temperature.
O2 - Oxygen Sensors ? air/fuel ratio via exhaust O2 content.
IAT ? Inlet Air Temperature Sensor ? temp of air entering intake manifold (and therefore the air's density).
TPS ? Throttle Position Sensor - throttle blade position (opening).
IAC ? Idle Air Control Valve - the IAC supplies metered air at idle, its sensor reports the solenoid plunger position.
MAP ? Manifold Air Pressure Sensor - intake manifold pressure (vacuum) and therefore engine load and altitude.
CPS ? Camshaft Position Sensor - rotational position of camshaft and therefore valve/stroke timing.
KS ? Knock Sensor - engine knock or ping, used to retard timing and prevent pre-ignition.
All of these sensors play a vital role in engine operation and are used by the MEFI-4 ECM to sense a variety of operating conditions.
The outputs from the MEFI-4 ECM are:
MEFI-4 Outputs:
EST Signal (Electronic Spark Timing) - to fire the coils / spark plugs.
Injector Driver - to fire fuel injectors.
IAC Stepper Motor Control - Maintains perfect idle speed with the IAC stepper motor.
Fuel Pump Relay - Intelligent control of the fuel pump based on fuel pressure and engine status e.g. shut down fuel pump and therefore engine on overtemp, low oil pressure, engine overspeed, etc.Check Engine Lamp - ECM turns on warning lamp when it detects a problem condition. It also stores a "diagnostic trouble code" or DTC which can be read by a scanner.
Tachometer Signal - to drive the tachometer.
Fun Times said:
Looking through the service manual you will not typically find a code 81 listed to be able too start a typical diagnostic procedure. But code 81 does exist and there is a list of codes but the problem is they are not published. They only show up on the scan tool when some sort of problem arises
Hey I just ran across the MEFI 4/4B code 81's,
http://www.pirate4x4.com/tech/billavista/MEFI/images/MEFI-4 Trouble Codes.jpg
For future reference there's lot of good info on the MEFI 4/4B ECM's including a very helpful PCM diagnostic manual in the link below,
Pirate4x4.Com - The largest off roading and 4x4 website in the world.
Good luck.