Golf III injector signal?

[Quezacotl]

Hello!

I just installed the MPGuino on my VW Golf -94 1.8l 66kW Mono-Motronic system. One-point injector.

I found the VSS signal.
And i found the injector plug, 4 pole. 1 has voltage, and 2,3,4 has 0V.
So i picked the rightmost pole, where is 0V, but it does'nt bring anything to MPGuino.

Should all the three poles give reading or just one?

And does anyone know about this car?

And another thing, how soon it is supposed to give litre readings when you start using it? Immediately? Even though the starting values are garbage?

Thanks

[mwebb]

use T pins on the Injector connector


use a test light connected to battery positive , with engine at idle ,
connect to each of the injector wires
1 wire will have a signal which will blink the light , faintly ,the duration is only about 2ms
that is the pin to connect to the MPGuino

or use a scope
this is what you will see on the correct pin


connect the scope ground / negative test lead to the battery negative

[Quezacotl]

I dont have a scope, but i do have a frequency meter. Dont know if it will help anything.

I switched to second wire yesterday, and now it outputs some readings, atleast it seems it picks up something. Hard to know on my 5km work trip
It displays something on current/tank, but only flashes instant at sometimes.

I have understood that the "instant" should continuously display the ongoing average consumption on the road, right?
I tried to adjust the µSec/Gallon to show more truthful than garbage, to see something, but instant stays only flashing occasionally.

Am i doing right when i drive little, then adjust it so that the "tank MPG" shows about 7 litres(my average), and then it should show "instant" and all as nearly truthful?

(and yea, i will calibrate it accurately as soon as i go to fill up)

And by the way, i calibrated the speed signal couple days ago

EDIT: Hmm... i just tried the flow rate calculator, and it would guess 384.000.000, while i adjusted it to only something like 140.000, strange... but well, i will try that value if it gives better results, once i get home from work.

[Quezacotl]

The stealer connector i was using to tap into injector signal, was faulty. Now it works good.

Now i have the current and tank readings working, but only thing that does'nt work is instant MPG, no matter what screen i have.

Anyone know what could be the problem? Hard to believe it's hardware problem, since all other things are working. Or could it?
And i have JellyBeanDriver's aka dschmidt's version, based on DCB:s v0,86 code, according to the dschmidt's site.

It goes like: When i start, not yet moving, the "instant MPG" is 99999, and when i move, the "current MPG" starts to decrease from something like 20l to 6l, as it's stabilizing.
(dont remember what the metric abbreviations are, but anyway)


But for someone else with same car, helping tips so far:

-Injector leads: (looking at the connector at front side) [12V], [something], [the signal], [something]
-VSS: 12750 (starting value)
-INJ: 250000 (starting value)

Will post more accurate inj, and VSS while i get to write them up

[JellyBeanDriver]

Sounds like you have VSS and Inj swapped.

[Quezacotl]

Originally Posted by JellyBeanDriver

Sounds like you have VSS and Inj swapped.

I am pretty sure it's not. I remember that i made sure that i have them right way.
And that supports also that fact, because i first connected the speed alone, and drove(is that a word? ) a little, then by trial and error i managed to connect the injector signal.
I can check them again, to make sure, if i have somehow swapped them at some point, dunno when would that have happened.

Now i have driven like 300km, and l/100km is getting more truthful, but the instant still reads zero.

So, swapped wires is one logical cause, what else could?

[Quezacotl]

I disconnected injection wire, leaving VSS connected: it shows the speed only.

And for curiosity, i swapped Inj and VSS: i got it to show nearly truthful values, including instant
But now, naturally, it picks the speed from injector, and injector from speed sensor, so it wont work. I will swap them back.

Could the other values in settings affect the instant? Could injector delayµs affect that? I gotta try to fiddle with that.
The "current l/100km" is stabilizing slowly, sometimes from 200l/100 to 11-6l/100. Meaning that it updates too slowly, i think. And that's how injector delay adjusting would work?

EDIT: Yea, adjusting injector delay did work. Now i only need to calibrate it better. It was 500µs default, 150 does not display instant, 140 does. Any suggestions for this? Just testing, testing...?

[Quezacotl]

Now it works quite reliably. So accurately that i know now that the blower at max stage decreases fuel economy by 8% and first stage 1,6%

As soon as i have got it calibrated fully, i will try the free air intake mod (70mm hose from airbox into fender), and see how much it will really save