cylinder contribution issues

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cylinder contribution issues

Postby MD tech » Thu Jan 12, 2017 4:22 pm

I was attempting to run the cylinder power balance test on a 2004 ford f250 diesel. I cannot get the test to acquire a good signal. I realize that the software does say that it doesn't work on all vehicles, but I was wondering if there are any tricks beyond what is listed in the software to get it to read. I tried all electrical loads on, disconnecting one of the batteries (dual battery truck) I even tried a load tester at 75 amps and it still would not read.
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Re: cylinder contribution issues

Postby STC » Thu Jan 12, 2017 5:11 pm

Hi MD

You are not the only one having those issues, Smart Charge etc. gets in the way. Cylinder Balance on a running engine can be achieved by hooking onto the Crank Sensor and adding a Math Channel.

The advantage here is that you can deploy another channel on Diesel Injector or Petrol Spark (Primary or Secondary) to get individual cylinder identification.

Call it evolution :D

Hope that helps.
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Re: cylinder contribution issues

Postby MD tech » Fri Jan 13, 2017 4:44 am

Thanks for the reply, could you expand some on how I should set the math channel?
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Re: cylinder contribution issues

Postby MD tech » Fri Jan 13, 2017 4:55 am

I think I may have figured it out, I created a math channel frequency of channel a, will have to try it tomorrow.
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Re: cylinder contribution issues

Postby STC » Sat Jan 14, 2017 8:41 pm

think I may have figured it out, I created a math channel frequency of channel a, will have to try it tomorrow.


When you get it to work and see it for the first time it really is a "WOW" Moment. Life Changing !!!

You can use Frequency or there is a dedicated "Crank" function

Crank Delete.png


Remember that you can add the Math Channel after you have taken the capture to a saved waveform, that is the beauty of it.
Don't try to have it running as you run "live"

Here is a link to a tutorial

topic11511.html
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Re: cylinder contribution issues

Postby MD tech » Mon Jan 16, 2017 12:09 am

Wow, I did not see your reply until just now, but I ran the test using the frequency function and an injector coil current as the trigger. It clearly showed a drop I frequency on cylinder 5, I was able to overlook the dropout from the missing teeth, as it was just after tdc. I will have to try the crank channel sometime. thank you for the help, I think I like this better than the alternator based contribution test.
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Re: cylinder contribution issues

Postby STC » Mon Jan 16, 2017 5:29 pm

If you have not already, then have a little play with the "Vertical Zoom" on the Math channel. Helps to paint a Prettier Picture.

The "Missing Tooth" drop out can be solved with this reluctor ring with 60 teeth (£4 on ebay).
60 tooth.jpg

Mount it on a strong magnetic base and stick it to the crank pulley (it wont work on all cars) then use an inductive crank sensor on the end of a stick to get a waveform.

Be aware if it flies off it will hurt !!!
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