Irvatron

urban_dk is correct

You need the white wire that goes to the gauge as this not only is 0-5V but has the correct drivers in the W/B controller to supply the correct amount of current to supply signal to both the gauge and the EMU.

 

Thanks Mark.

I think the initial confusion lied with...

I thought i would have the white and black wire connected upto the gauge/controller and tap off those two wires.

In the AEM manual, for 4pin connector it mentions the white wire and blue as optional

So now i think i should have both the 4 pin and 6 pin connectors connected up the the gauge/controller, but disconnect just the white wire from the gauge/controller (so it doesn't go into the gauge any-more) and run that to my A/F harness and ground the other wire to where everything else is grounded in the car including the gauge etc.

Seems logical?

Heres a pic i made from the manual:



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However i now read the output as an EM is non linear.

Been bloody bent over my car for 9 hours today as i refitted the supercharger (me and my mate rebuilt it), cleaned exhaust and reburnt blue on the exhaust tip and serviced the car .

 

Doesn't seem logical at all, actually. Remember, the white wire is an OUTPUT from the gauge itself. You are making this too complicated.

You take the white wire from the 4 pin connector and wire it from the gauge to the option port on the EMU. You can tap the black wire (GND) going into your gauge from the 4 pin connector in order to have a common GND between the two.

Repeat - the white wire needs to still be going to the gauge, because that is where the signal is coming from. Do not disconnect!

 

Doh So I've been a retard and made this far more complicated than it is I dont know what i was thinking!.

Looked at the wiring physically and there is just a blue and white wire coming from the gauge which were capped off and hidden in the thicker wiring , once i found those all was revealed.

I plugged in my harness i made and tested it. I connected the white wire and ground wire and bingo it shows the AFR, however it seems a little out. Its -1c here and pitch black so didnt test it too much.

For example the gauge readout hovers around 13.0-13.2AFR (starting the car from cold and it had been running for approx 1 minute when i was monitoring) but the AFR on the greddy logger software is 12.6 - 12.9 and sometimes even more out but not by a much (-/+ 0.1).

I tried in the settings altering the range from 10.00 to 20.00 and 10.00 to 18.00 and it didn't make much of a difference. I did notice however with no wires connected the Greddy logger thought the AFR was 10.2. I do notice whilst an OBD2 logger would show coolant temperature at a normal 84c the greddy generally thinks its 76/8c.

I am reading ATM about the bosch sensor on the AEM not being linear. I found in the AEM manual that its definitely 10.0 to start with but it mentions 19.98 (0.0 - 4.99v) in one section, and another section 10.0 to 18.5 (0.0 - 4.25v) - so i will test these tomorrow. Maybe there's some computational delay or loss?

Hopefully in future this will be useful for other people, when i sort it.

Any one any other ideas?

Thanks

 

The best thing is to make sure your gauge and the greddy A/F harness share a common ground. Other than that, there isn't much you can do if it is off a few tenths of an AFR. I believe the range is simply 10 to 20 for 0v to 5v like you implied. You can fudge it a bit but it may make you off in another part of the A/F function.

 

Unfortunately the AEM UEGO and EMU combo didn't work too well, it fluctuates too much.

 

Post a log? There should be a decent amount of fluctuation in closed loop.

Or are you more worried about the discrepancy between what is displayed on the gauge versus what is shown in the Emanage software?

 

I have logged it Brad, for example my wideband and the dyno wideband values more or less the same however the log has it showing say 13.1 when its actually 12.2.

Of course there will be fluctuation in closed loop, but I'm tuning open-loop and this is where it fluctuates when it should be more or less steady.

 

anybody have the greddy ultiamte software?

 

You can download it from their website. It is free.