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Ej 22 vss issues I think..
vduboy - March 28th, 2017 at 08:09 AM

So I have got my Subarugears/Ej22 conversion running and driving, the only issue I have is a intermittent code 24 (idle air control valve open or short)
I have cleaned the valve and it was spotless, functions perfectly at a cold start. All continuity checks out perfect.
The only thing that came up regularly in a google search was the vss issue.
The vss Todd supplied with the box runs the gauge perfectly, does anyone know if it is compatible with a older 1996 Ej22? In the old liberty it did have a two wire speedo sensor running to the old gauge cluster then one signal wire running back to the ECU. I was under the impression I could run the signal wire out of the new vss straight into the ECU and the speedo?
Any thoughts?

psimitar - March 28th, 2017 at 05:36 PM

The speedo transducer may be causing harmonics on the signal wire and making the signal disappear from the ECU very briefly but enough to set the fault codes flag. Only real way to check this is with an osciloscope as a multimeter scan rate and averaging ability make small fluctuations undetactable.

vduboy - March 28th, 2017 at 07:20 PM

Quote:
Originally posted by psimitar
The speedo transducer may be causing harmonics on the signal wire and making the signal disappear from the ECU very briefly but enough to set the fault codes flag. Only real way to check this is with an osciloscope as a multimeter scan rate and averaging ability make small fluctuations undetactable.

I did think this too, so I disconnected the speedo and all the same, I think the issue with mine is I am only getting 3 pulses per revolution of the wheel when the Ecu I believe is after 4 to 5 pulses depending on the source. So I tried a Jaycar speedo corrector but it fails to see the signal from the hall effect sensor.. :grind:
I have ordered a NPN hall effect sensor (like Joels wheel of death) to just run the ECU's signal as the VSS runs the speedo perfectly.
Hopefully that works!!

vduboy - March 29th, 2017 at 05:45 PM

I have trialled and errored all week so far... got me absolutely stumped as to what I have f@#ked up.. shitting me to tears actually!
I have doubled checked the new TPS, made a new 6 pronged pick up wheel to make up for the difference in tyre size, fit up a separate npn inducer pick up just for the ECU's VSS input.
I don't know whether the thing isn't receiving enough pulses/wrong output 12v/5v (it currently gets 12v square wave pulsed)
I even tried manually bumping the idle stop screw which I know is a massive no-no but I had the s#!ts!
At the moment I am thinking I should be feeding 5v to the pick-up instead...?

vduboy - March 29th, 2017 at 08:01 PM

I don't know if having 29" tyres and 4.11 diff ratios makes any difference as well... so bloody close to being done!!!

psimitar - March 30th, 2017 at 09:05 PM

Anything to do with the ECU will be 5v and not 12V when it comes to sensors. Hopefully that's the issue :)

vduboy - April 1st, 2017 at 07:48 AM

Well I did a few things while I am waiting for my obd adapter lead to come in, still not sure what else I need to talk to subarus ssm protocol, I changed the input to the vss sensor to 5v, no change. Cleaned the afm, no change but running smoother, added a clutch switch on the neutral line, massive improvement! But still throwing the code so I earthed the neutral switch and bypassed it, no codes and no stalling! Wtf??? Is this telling the ecu not to look for a vss? I will get a fault 51 neutral switch staying on whilst in motion but it doesn't trip the CEL. So I can live with that until I figure out what is going on with the neutral switch. It does seem to have unusually high resistance. Engineer is coming around today so hopefully all is sweet!