> From: Luis Moreira > Subject: RE: [EE] Injector Testing > Hi James, > Not quite the question I was asking, I have access to plenty of tools lik= e > that one at the moment. In fact I use one like that from fluke all the > time, I also have some tektronix ones. > I am more interested on the manner of the testing. > I deal mostly with 4 cylinder vehicles and although I intend to expand th= is > test setup to 6,8 or even 12 cylinders, this is ideal to get the > measurements into a four channel scope, which will show the four injecto= r > signals and timing in relation to each other. In my opinion in one go I > could get quite a lot of info just from this. The breakout box would allo= w > me to observe the injector signals with them still connected to the ecu. > Observing the current would also give me info on injector resistance and > any other issues. > As an example, I am looking at a Vauxhall Vivaro, which had a confirmed > faulty injector changed. After they changed it, the problem is still ther= e > and instead of a cylinder X miss fire I get a intermitent injector contro= l > short circuit fault. I suspect the bad injector may have damaged the ECU > output driver stage/current sensing circuit, but before I send the ECU fo= r > repair I need to reassure myself that the rest of the circuit > (wiring,connectors and injectors) are fine under load, Now getting to the > injectors on a van like this is a pain and I only want to remove all the > bits to get to them a couple of times. With a breakout box I would get al= l > the info at once. > As I haven't found any setup like this I am just wandering if this as wor= th > while thing to persue. > Thank you. > Luis > On 27 Feb 2015 18:10, "James Holland" wrote: >=20 The breakout box is a good idea but I don't see a big advantage of having m= ultiple current probes. It should be pretty easy to spot a bad injector fro= m its current waveform if its an electrical failure rather than a blockage;= the peak current and the rise time tell you all you need to know.=20 The LEM sensors that I've looked at measure AC current only, if you do deci= de to build a setup then sensors that can measure the DC component as well = would give a better representation of the waveform. James =20 --=20 http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .