FAST AND EASY HOOK UP
LOCATE PROBLEM CYLINDERS THRU EXHAUST SYSTEM PULSES.
COLD CRANK ENGINE TEST DETERMINES CORE ENGINE
PROBLEMS- VALVE LEAKAGE, CYLINDER COMPRESSION.
HOOK UP TO FUEL PRESSURE REGULATOR AND CHECK FOR
INJECTOR PROBLEMS.
Theory of Operation
The FirstLook Diagnostic Sensor is unique because it looks at
pulses in engine airflow, allowing you to display "the pulse of
your engine" on standard scope equipment. While scanners
interrupt the information they receive from engine sensors and
engine analyzers tell us what the ignition system is doing, it is
difficult to see what was
actually
happening in the engine
without intrusive tests. With the FirstLook Diagnostic Sensor in
your diagnostic arsenal it will now be possible to see what is
dynamically occurring in your engine.
Pulses vary over time depending upon the stroke cycle of engine
It is important to try out your FirstLook Diagnostic Sensor on a
good engine to understand what is normal. Cause a basic
problem by disabling a plug or injector and see the effects on
the waveform. What you are looking for is a consistent
pattern, do not try and diagnose every little bump in the
waveform. It is the major deviations from normal that you
need to address.
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Fuel Injector Pressure Regulator Test
1.
This is one of the fastest ways to see if there is a volume difference
between any of the injectors.
2.
Just remove the vacuum line from the fuel pressure regulator
and plug it. Now hook up the impulse sensor to the fuel pressure
regulator nipple.
3.
Trigger the scope on #1 injector. There is no off set to think about
here. They will show up in the correct fire order.
4.
Set the trace up with the pulse sensor to either lv or 2v ac scale,
time is consistent with all other tests. Idle 200 ms, 1500 RPM
power brake test 100ms.
5.
As the injector pintles open and close, the sensor reads the
pressure drop that the fuel pressure regulator diaphragm creates.
6.
All that is left is to see is which injector amplitude is higher (more
fuel) or lower (less fuel).
7.
As with all of the tests mentioned it is very important to practice on
known good cars and create certain conditions to see how they
compare.
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