ELECTRICAL COMPONENT  SENSORS

AFP= Air/ fuel  ratio.

AfS= Air/ fuel ratio sensor.

CEL= Check engine light.

COP= Coil on plug.

CTS= Coolant temperature sensor.

DIS=Distributorless Ignition systems.

DTC= Diagnostic trouble code.

ECM= Engine control module.

ECT= Engine coolant temperature.

ECU= Engine control unit.

EFI= Electronic fuel injections.

EFIE= Electronic fuel injection Enhancer.

EOP= Engine oil pressure sensor.

HEGO= Heated exhaust gas oxygen sensor.

IAT= Intake air temperature sensor.

MAF= Mass air flow sensor.

MAP= Manifold absolute pressure.

MAT= Manifold air temperature.

MIL= Malfunction Indicator Light.

MMW=Milliliters per Minute per Watt.

O2S= Oxygen sensor.

OBD-2= On board Diagnostic system.

PCM= Powertrain Control module.

PCV= Positive Crankcase Ventilatio.

TPS= Throttle position sensor.

VCM= Vehicle control module.

VSS= Vehicle speed sensor.

WOT= Wide open throttle sensor.

NOTE:
- Less vacuum= more pressure.
- kilo pascal's KPA 100 KPA=1 Atmosphere.
- Cranking turns engine slower so there us less vacuum.
- Cranking the throttle open will have very little or no vacuum/



Outline: On- car Fuels Practical


Review four stroke cycle
Engine conditions, engine needs:
Rich, lean
cranking, cold, idle, cruise, power, deceleration

Basic:
what it takes to make a engine run.

-Mechanical: Pistons, cam,valves,belts. etc
-Fuel: pump,flow,injections, sensors, ECU
-Air/ exhaust: idle speed ,CAT,EGR,PCV, etc
-Ignition: Spark.plugs,timing, igniters,Ht leads,etc







Fuel pressure
The fuel pump, pumps the fuel from the fuel tank through the filter to the fuel rail and then into the cylinders via the injectors. The pressure of the fuel is controlled by the fuel pressure regulator on the end of the fuel rail. The fuel pressure regulator works with vacuum from the engine. The faster the engine goes the less vacuum it creates in the manifold which means that the regulator would be closed more. When the regulator closes it creates a higher pressure in the fuel line (by restricting the flow or blocking off the fuel at the end of the fuel rail)  which forces more fuel through the injectors into the cylinder.

Experiment

We connected a fuel pressure gauge to the fuel line after the filter. We started the engine and checked the gauge the reading was about 2.5 bar when we revved the engine the pressure increased to about 3 bar. To simulate the engine at full speed the vacuum hose can be disconnected from the fuel pressure regulator.

Reflection

The fuel pressure gauge can be used to see if the fuel pump is working and to check if the fuel pressure regulator is working properly. when the engine is idling and then the regulator vacuum hose is removed the pressure should increase in the fuel line. If it remains the same there may be a problem with the fuel pressure regulator.