Thursday, September 30, 2010

WS4 Fuel Pressure and Flow

The fire extinguishers can be found in the corner of the class.
The fuel pressure spec on the toyota A4-fe is 265-304KPa.

To install the pressure gauge, you must relieve the pressure in the system first. You can do this by removing the fuel pump fuse and then cranking the engine. The gauge was properly installed and there was no fuel leaks.
The gauge read 200 KPa.
At idle the gauge read 25o KPa.
Maximum pressure of 400 KPa.
WOT of 300KPa.
The Residual pressure was 250KPa.
The flow is 2.2L per min.

I then uninstalled the gauge. I refitted the hoses, double checked them.
I cranked the engine to check for leaks before starting it. It ran fine.
It is important to know how the fuel system works, as it can help to find leakages and/or blockages.

Symptoms of a vehicle with these problems:
Low fuel pressure:
It would be unable to idle.

Low fuel flow:
The car would run lean as there is not enough fuel being injected.

High fuel pressure:
The car would run rich as the injectors would be forced to stay open longer than necesscary.

Faulty fuel regulator:
Car would be jerking, or just not run at all as it starves for fuel.

1 comment:

  1. Your symptoms need another look, for example high fuel pressure does not affect the open time for petrol fuel injectors, also you need to exp[lain how these faults would affect the drive-ability of the vehicle (in detail)

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