Diagnostic Socket?

[oldkiteman 6]

Finally got my GTI6 running,but it sounds to be running very rich,causing it to stall.The trouble is,its a phase2 vts engine,306 loom off ebay and unknown ECU,I would like to plug a diagnostic tool in to get some live data rather than change bits hoping to cure it.

The problem is that I cant find wires 140 and 141 going to the big round plug.There are only 17 wires going to the big plug.

According to autodata,140 and141 should be connected to the ecu on pins 12 and 31,I have tried to

separate the plug to check if any wires are connected,but it wont come apart without damaging it.

Has anyone managed to do this,and if so,how?Rob.

 

[oldkiteman 6]

Just had a thought,could this loom be from an early 306 without 16 pin diagnostic port?could the diagnostic plug be this green one which is near ECU plug?

[rikky 37]

I found them easy on my loom when I did it. Infact I regret not putting the OBD on there. So yeah possibly a P1 loom. And the plug was near the ECU yes on the P1, or was on my P1

 

(my loom currently is off my P3 gti6)

Edited August 5, 2015 by rikky

[Anthony 1,003]

2-pin green plug near the ECU does sound like the diagnostic plug on a Phase 1 306 loom.

 

The functionality is there on the ECU though for the 16 pin diagnostic socket, but you'll need to wire it up.

 

Remember that the 16 pin diagnostic socket on a GTi-6 isn't OBD2 compliant and most cheap code readers won't work. You'll need something like Peugeot Planet / Lexia 3 (the dealer diagnostic software) to read data from it.

 

On a related note - if it's a Phase 2 VTS engine, have you swapped all the required bits over to Phase 1 VTS / 306 spec? The fuel injectors and fuel pressure regulator are both different on a Phase 2 VTS for example, and likely wouldn't fuel properly using a Phase 1 ECU.

[dobboy 231 2 Cars]

The knock sensor is also different, it's white on vts (two pin) and black (three pin) on gti6.

 

If you look on the guide on here, i posted the pin/wire numbers that were on my big brown plug, it might help you.

[oldkiteman 6]

I have tried an old snapon scanner with the correct peugeot module and it wont communicate via the green 2 pin plug..I think I have an ECU which is designed to communicate via pins 12 and 31 through a 16 pin plug and a loom which has no wires connected to 12 and 31 and is supposed to connect via the green 2 pin connector.So neither system works.

The only sensor that i have swapped is the knock sensor for a 3 pin one.Everything else is P2 VTS including the MAP sensor which i had to solder in the vts 3 pin oval connector from the vts loom.

Do you think i will every get it to run properly like this,or do i need to change injectors,pressure reg,sensors,loom or ECU.

Yours,feeling a bit pi**ed off,Rob

[ade 4wd 11]

Have you checked that ECU pins 12 and 31 go to that green 2 pin connector using a multi-meter?

[oldkiteman 6]

Have you checked that ECU pins 12 and 31 go to that green 2 pin connector using a multi-meter?

Good call!Just checked continuity on 2 wires on green plug and they go to 12 and 31.I have also stripped back the insulation and the wires are numbered 141 and 140.

So I intend to connect a permanent live to terminal 16,earth connection to No 4,wire 140 to terminal 7 and wire 141 to terminal 15 of the diagnostic socket.

I will let u know if this works.Rob.

[oldkiteman 6]

Just wired it up and it works.Snap on scanner will read it.There were 2 codes,canister purge circuit and MAP sensor .Looking at thelive data without the engine running,the MAP is reading 500 millibars instead of about 1000.I am hoping this explains the rich mixture.Looks like I need a MAP sensor.Rob.

[welshpug 1,657]

yep, less vac with an open throttle so would add more fuel, though has a TPS too.

[oldkiteman 6]

Think the TPS is OK.Looking at a graph of operation produces a nice straight line from closed to full throttle.