VAG-COM and the Mk3

DelG40 · Post by **DelG40** » Wed Jan 18, 2006 1:47 pm

Has anyone ever used it with the Mk3? Does anyone know if it can communicate with the program.

Currently trying but to no success. Not getting any information back from car.

Do you have to use the actual VAG-COM communication tool? See we've made our own w/ ELM chip, etc. Just wondering if the authentic one has its own authentic "Hello, it's me. The real VW" message.

richandhazel · Post by **richandhazel** » Mon Jan 08, 2007 7:58 pm

I know this question was asked a year ago but as I have just tried it and had very little success, I thought I would raise the subject again.

I've managed to get it all connected up ok and connection is confirmed by VAGCOM. However, none of the controllers can be read so I'm wondering if you need to read this via the LED's on the cable. If so, anyone know how to interpret the LED's flashing?

richandhazel · Post by **richandhazel** » Mon Jan 08, 2007 8:10 pm

Ok.........in my previous surfing and due to vehicles I've had in the past, I remembered that I came across this:-

http://20v.org/fault.htm

What do you reckon the chances are that they might actually be the same?

richandhazel · Post by **richandhazel** » Mon Jan 08, 2007 8:50 pm

hmmm, just found this too;-

http://www.clubgti.com/forum/archive/in ... 50225.html

DelG40 · Post by **DelG40** » Tue Jan 09, 2007 12:39 am

Wow... how old is THIS topic!!

Apparently you can only read fault codes from the Mk3 ECU and nothing else. So VAG-COM is a bit overkill and it doesny really work with it anyway

richandhazel · Post by **richandhazel** » Tue Jan 09, 2007 10:09 am

I already have the VAGCOM for the mk4 Golf so the easiest way for me to set something up for interrogating the ECU on the Polo was to get hold of the additional 2x2 adapter.

Going to try it again now and see if I can interpret the led's.

By the way, the reason I'm doing this is:-

Basically the car starts on the button and idles fine. As soon as you press the accelerator it overfuels and stalls. If you're quick enough in letting go of the accelerator so that it drops back to idle it'll recover and idle fine.
It only seems to run properly once fully up to temp.
A couple of times it has overfuelled so much it has flooded itself and will not start for a good 15 minutes.

I have replaced the blue temp sender...........no fix.
I have tried disconnecting the lambda sensor.............no difference.
I have tried leaving the battery disconnected overnight............no difference.

richandhazel · Post by **richandhazel** » Tue Jan 09, 2007 11:04 am

Well I have tried it again a number of times and am getting a consistent result that doesn't make any sense to me whatsoever:-

4 short flashes
11 long flashes
4 short flashes

Going to take it for a spin shortly and see if it has made any difference i.e cleared the codes, reset anything

minis84 · Post by **minis84** » Wed Jan 10, 2007 8:53 am

from having had this problem myself the only two things it can really be are the AFM or the throttle position sensor, as these are really the only two major components that are linked to the throttle. However I would be inclined to say throttle position sensor.

But if you can determine from the fault codes what the problem is then it would save some time and money in faffing around changing components I guess.

richandhazel · Post by **richandhazel** » Wed Jan 10, 2007 9:36 am

Well I have just tried the same Vagcom setup to read a mates Audi codes and with that you could get into the engine module and actually read and clear the fault codes. The Audi was slightly newer, but it did use the same 2 connectors so I suspect that the LED test that I'm doing is simply that, an LED test and not the fault codes. So, it doesn't look like vagcom is able to access my ECU for some reason. I will give it another go today.

If the problem still exists, my next plan of attack was to clean the throttle body and looking into testing the position sensor.

CARPY25 · Post by **CARPY25** » Wed Jan 10, 2007 9:53 pm

i had a major over fueling problem on my old astra gte took ages to sort in the end turned out to be a fuel pressure reg that had a hole in the diaphragm and the vacuum pipe was sucking fuel into the inlet manifold after the throttle body when it went so bad the car would only rev and not tick over but before that hole got so big i was have all kinds of strange running problems

Rob

vikash · Post by **vikash** » Sun Jan 28, 2007 8:28 pm

hey just thought i add that i was trying to use vagcom and it never worked for me...

but vwtool did work and i could read the errors off the ecu... it would erase the errors but came back with an error saying ecu doesnt support it....

but it does work.. dont know where to get vwtool but i got it when i bought my cable from hong kong