I brought 4 used subaru wrx injectors which should flow 440cc/min@3bar. I wanted to make sure they were still performing to spec rather than risk
running one cylinder lean.
Sent them to an outfit advertising on ebay - name withheld for now to be 'ultrasonic cleaned and volumetric flow tested at 3 bar'. Cost £60
for 4 injectors.
Sent them away and they came back nicely cleaned but with no test report. So I got in touch and they said they're all good don't worry
about it. I insisted so I had to send them back and they came back with a test report which says:
back leak 0mL
Idling test 90mL 90mL 90mL 90mL - 4minutes
Mid range test 78mL 78mL 78mL 78mL - 1.20 minutes
Full range test 50mL 50mL 50mL 50mL - 20 seconds
Simulating low speed 53mL 53mL 53mL 55mL 55mL - 1.20 minutes (where did this 5th injector come from?!)
Accelerating 95mL 92mL 93mL 92mL 95mL - 1.20 minutes (again extra injector)
Simulating high speed 95mL 95mL 95mL 95mL 95mL - 1.20 minutes (5 again!)
Electric test 12.6 12.4 12.5 12.5
I assume the full range test is the important one and 50mL/20 seconds = 150mL/min which is one third of the rated flow. I'd expect that on one
dud injector but not on all 4 and with consistency. So I reckon that they didn't test them at all but just made up a load of numbers that would
look plausible if you didn't pay too much attention and then sent them back to me
I do not know about the figures, to test mine I just made a simple rig, fuel pump, tee pice regulator and a couple of big jars.
I powered it all from an old battery charger with just one diode instead of a full bridge rectifier so this gave 60 pluses per second for 50% of the
time then timed how long it took each injector to shift 1/2 litre of fluid.
You get to see the spray pattern and can confirm that they all are similar flow rates, in the event a couple were a bit dodgy but looping with
cellulose paint thinners sorted them out.
I use Mr Injector and he always provides a printed spread sheet with figures and pass or fail results.
That's a very consistent set of figures for used injectors
[Edited on 7/5/17 by Ben_Copeland]
An on car balance test works for me , you need a pressure gauge and an injector pulse tool both of which are fairly cheap off ebay.
As it a method worth sharing I will post links to a Scannerdanner video on it.
Paul "Scanner" Danner Injector Balance test.
Cleaning the injector
Another car
[Edited on 7/5/17 by britishtrident]
quote:
Originally posted by luke2152
I reckon that they didn't test them at all but just made up a load of numbers that would look plausible if you didn't pay too much attention and then sent them back to me