Understanding GDI/Piezo Flow Test Reports
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Reports are broken into individual tests with colors to represent results. Each test plan is specific to the injector and defines a flow characteristic defined in cubic millimeters per stroke (mm^3/strk). It defines the injector flow rate to maintain demands of the engine needs.
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Good - Green color means Injector operated within its flow corridor.
Best - Blue color means Injector operated within a narrower range centered around the middle within the required flow corridor.
Fail - Red means it failed to operate within the requisite flow corridor.
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​The main tests you will see are as follows:
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LKT.01: Low pressure leak test
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LKT.02: High pressure leak test
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IVM.01: Full load measurement test
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IVM 02: Part load / emissions measurement test
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IVM 03: Low load/ idle speed measurement test
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IVM 04: Pre/Post injection measurement test (not always present)
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Item of note:
Red result does not equate to a bad injector. It can, but you need to look at the result to understand what it is doing. See below for more details.
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​Our POWEWRFLUSH system often changes red results to green, and green results to blue. It doesn't happen every time, but if we can't make it happen, then it's not possible.
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GDI/Piezo Report Test Results
FLOW CORRIDOR:
You can see on the tests I marked expected flow corridor, green bracket, blue bracket and red bracket.
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Green bracket represents the acceptable range for the injector operating given the test parameters, considered good
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Blue bracket represents a narrower range for the injector operating given the test parameters - considered better
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Red bracket in this case you can see it temporarily dips above the top range. It may run rich momentarily or it may fail to meet minimum values.
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The Number to the right, shown in orange on the test above, is the set of values the injector actually operated at. High/Low/Mid point.
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If you look at IVM.01 and IVM.03 above they are both performing within spec with IVM.03 performing more optimally, but Green or Blue are injectors that successfully passed the tests.
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If you look at IVM.02 above, it has slight deviations above the top line with a number defined, it means it can occasionally run rich for that specific condition. I would not say that injector needs to be thrown out, it may or may not be an issue depending on your needs.
If you look at IVM.07 at the bottom of the tests above, it is failing to perform even at a basic level. I would consider that injector fully bad and needs to be replaced.
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OTHER VALUES:
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STRK - is the frequency of the injection per min.
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Inj.1 - Is the number and period that we open in microseconds that the injector is made to spray. There can be more than 1 injection period.
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​hp(bar) - High pressure value, Leak test below show 70 & 170 BAR or 1015 & 2538 PSI
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