Maintenance of the
represent one of the focal points of a Gas System.
Their malfunction could be the reason for major problems and even a
risks for driving.
their Periodic Maintenance
is essential, and linked to many factors:
if the filtering is accurate, the filters will clogs easily, but the
Gas Injectors will be less dirty. The Gas Tanks, although new, often
contain dirt that contribute to dirty the filters and to reduce their
functionality: as we all know, the filters work well when they are
clean, but they do damage when they start to get dirty, therefore: watch the Maintenance of Filters
not all Gas are equal, in fact to the producers is given the right to
unfortunately with a certain amount of discretion, the percentages of
its components, sometimes also as a function of the ambient
temperature, that if too low would impede its normal use. Fortunately
the ECUs equipped with OBD control, performing automatic corrections,
at least do not suffer from such harmful variations. Sometimes
even the Gas Tanks, at Service Stations, are not thoroughly cleaned and
with the Gas dirt of various nature
number of Hours of Operation,
stated by the Manufacturer: Some injectors are sold for 30,000
kilometers, others to 100,000 kilometers, etc ... depending on the
characteristics of the materials they are made and the technical
taken to reduce the wear.
softwares allow you to set the number of operating hours before
reporting the need of maintenance.
To obtain an average value of the hours to the next maintenance,
depending on the routes and the speed, for example 50 km/h as average,
for 100,000 km the calculation is:
Km / 50 Km/h
= 2000 hours
type of Injection:
Semi-Sequential Injection (2 openings per Turn) increases the wear
and will reduce further the work hours, a Fullgroup Injection much more.
The ability to extend the life of a Gas
Injector also depends on the Control Unit driving it, which can
sometimes enhance the duration with certain precautions, as our POWERFUeL
The problems that can affect the correct
functioning of the Gas Injectors
are therefore substantially of two kinds:
- DIRT, which is solved with a good cleaning
- and WEAR, more complex to manage,
that is resolved by the replacement of worn parts or of the entire
After having understood that one of the Gas Injectors is leaking (see our
previous tutorial HERE ) let's take a look at how to disassemble
injector and to perform its cleaning properly.
First, to Remove the Coil, pry the e-clip
washer with a screwdriver
Remove the Coil
Unscrew the Shutter Housing
Remove the Shutter
Since each Shutter Housing is calibrated,
generally by robotic machines, to work with a specific Shutter,
it is good not to mix the various
pieces nor swap their position,
otherwise the Injectors will be not calibrated anymore and you will
recalibrate them necessarily! operation not so easy. For this reason we
strongly recommend to clean up a
Shutter at a time, and reassemble it each time, before putting
hands on the next.
Clean the Shutter-Housing, the Shutter
and the Spring by using only AIR and
White Petrol, like the one used for lighters, being careful not
to damage the rubber parts
or use only any Specific Liquids or
Spray, suggested by the Manufacturer, AVOIDING
ALCOHOL or SOLVENTS by which you risk irreparably damaging the
alternative is to use an oil, fluid enough to brush the components to
remove any encrustations.
After thoroughly cleaning the Shutter,
carefully watch the rubber parts and if they are damaged, or if you
see that, after reassembling, the Injectors still leak, it means that
it is necessary to replace the Shutters with
Before assembling, if necessary, also
replace the Shutter-housing o-ring seal, lubricating it slightly.
it was necessary to replace the Shutters, or if you doubt you have
shuffled the various Shutters, reversing their original position, you
will probably have to re-calibrate the Injectors. To be sure that this
operation is necessary, first try to keep the engine running on Gas
idle and, if it seems irregular and unstable, you will have to
re-calibrate the Injectors.
is to ensure that the excursions of all the Injectors' Shutters, on the
same engine, are equal to each other, otherwise an
Injector would supply a quantity of Gas different from another.
Unfortunately, the quantity of Gas dispensed substantially changes even
if the excursion is different of just a few hundredths of a millimeter!
For this reason it is a delicate operation that might jeopardize
the success of the cleaning just made.
a Calibration you have basically three different ways.
1 - BY
USING A DIAL GAUGE:
Gauges are available on the market just to calibrate Gas Injectors,
equipped with an adapter that allows a quick application on the rail of
the Injectors. Then you will not have to waste your time to lock both
the Injectors and the Dial Gauge in such a position that allows both a
precise measurement, and in the same time, a maneuver of adjustment of
the fixed core, by means of an Allen
for which every single Shutter must be calibrated depends on the
Injector Model used. These data are declared by its Manufacturer.
Generally the range is between 0.3 and 0.6mm, but the tolerance in the
adjustment is just ± 0.03mm, so great
caution must be applied.
you don't know this information, we suggest taking a new identical
block of Injectors, and measure its excursion. If also this is not
possible, take as a reference the average of the readings you can get
on the 4 injectors of the same old rail, because the most important
thing is that the 4 adjustments are the same. However, keep in
mind that a shorter excursion allows a better response, and the
injector will be able to open with smaller injection pulses, but at the
expense of the flow rate that will be lower; on the contrary, a larger
excursion allows a larger flow, but it makes it difficult to open the
injector with small pulses, unless you use our POWERFUeL
that opens any injector with less than 1 ms
perform the measurement, put the Dial Gauge probe in touch with the
rubber of the Shutter and zero the instrument by its reset button. Now,
to measure the excursion, it's necessary to supply power to
Injector Coil, that will attract the Shutter, allowing its displacement
and the relative measurement.
The Coils of the Gas Injectors are a few ohms, generally from 1 to 3
ohms, then the measurement operation
must be rapid enough to prevent the coil will melt! or that the
winding enamel will be damaged, causing a low insulation.
of using the 12 volts, it would be preferable to use a 6 volts power
supply, of a suitable amperage (4 or 6 Amps), in the absence of which
we suggest you to make a cable of this type, with 2 (or more) injectors
stress the Coils as little as possible, but using the 12volts, easier
to withdraw from the Battery of the same car; so they will trigger two
at a time, but with less stress.
Rotate the Allen Wrench until between the rest and opening position
there will be exactly the excursion necessary, for example 0.60mm for
Apache IG1 Injectors.
2 - BY A
A DIY (do it yourself) method, but quite
effective if it's well done, is to build a Calibration Apparatus in the
manner described herein. We didn't Patent it :) so you are free to use
First, you need to build a tool, made up
of a jar with airtight lid, like what
you use for jams, in which to drill 2 holes for the installation of 2
fittings for rubber hoses, for example with quick-connection for teflon
pipes. Partially fill it with water or colored liquid.
the Injectors to a Gas ECU, you can even connect only the RED wire
(Battery 12v), RED-WHITE wire (Key Switch, also on Battery 12v) and
BLACK wire (Battery Ground).
Connect the Injectors to an Air Compressor and adjust the Air Pressure
to approximately 1/2 bar, otherwise the quantity of liquid that will be
moved will be exaggerated and, despite the fact that the outlet pipe is
long enough, you might take a shower. If your compressor does not allow
this adjustment, interpose an old Reducer between the compressor and
Connect only one injector at a
time to the inlet tube.
Open the Software and in the Test window, when everything is ready,
click on TEST GAS Injectors to start the Test. In this way the Gas
Injectors will open alternately for 4 milliseconds, with intervals
of about 2 seconds, giving you the time to stop the Test when completed.
with a test if 1, 2, 3 or more openings of the same
Gas Injector are required to raise enough the Column of the Liquid in
Mark on the pipe, with a small piece of insulating tape or by a small
oring, the Arrival Point of the
Column of Liquid,
which will be also the arrival point for all
the other injectors, following the
same number of openings.
Obviously if the column stopped too high
or too low, compared to the first injector, rotate a little bit the
Allen Wrench and repeat the Test after removing the Injector pipe in
question and having waited that the level of the liquid in the
measuring pipe has fully dropped into the receptacle.
the Test is paused, if
the liquid inside the pipe does not maintain its stable level but it
goes up or down, it means
that there is a leakage on the Injector's Shutter.
For those who have the good habit to
perform these calibrations frequently, it is advisable to equip a
stable workbench, with Control Unit, Power Supply, watertight
container, pipes, etc. ready for use, which allows greater speed of
execution, without having to rebuild it every time, maybe adding a fast
air button or drain cock to reset the level in the pipe, without
bothering to detach the injector to perform more than one test,
creating in this way an accurate Gas
Injectors Test Bench, almost at No Cost.
3 - BY EAR:
A deprecable method, but nevertheless
practiced by those who have good hearing for the engine, is to keep the
engine running at idle and, with the help of the changing over of one
more Petrol or Gas Injectors, it is possible to "tune" the injectors in
the same way you do with a musical instrument
you had to Calibrate the Injectors, we recommend repeating the system
Finally, it must be stressed that in many
Countries, where labor cost exceeds the cost of the material, if
maintenance goes beyond a simple cleaning, the
complete replacement of the injectors with new ones is without doubt
the most affordable way, for the benefit not only of assured
efficiency, but also to reduce the dwell times in the workshop.