ECU repair advice

I hate to say this but i suspect its the injectors (maybe 1 or multiple) i was getting all sort of strange engine live readings--can your garage put a bore scope down to see what the injector tip looks like? mine showed two injectors very wet.
whilst the engine is under temp it will run conventional injection profile but once hot it will enter ultra lean and this requires a very accurate petrol mist at exactly the correct time.
It in my opinion is very unlikely to be ecu and that was one option with my car so i got an other and had the security chip swapped over. At no point did it ever have a code to hint injector issues. Good luck mike
 
High pressure fuel pump was the problem

Hi got the car back today took it away from the cheap end garage and took it to QS tuning in Haywards Heath . The are an independent Audi specialist who specialism is remapping ( they do A2 tdi)..... not cheap though £70 p/h.
They have lots of tech kit and diagnosed the high pressure fuel pump , replaced it along with the fuel pipe which I guess the last garage had turned the nut round on trying to remove it .

The issue always looked like fueling but the link to temperature really confused the diagnosis

Haven't been out on a run yet but all seems OK .
 
Hello guys, I don't know if it is the right place to write but... My problem is that I cannot read the ecu via vagcom cableI have an A2 1.4 petrol from 2001 and I get an ''no response from controller'' every time I want to read the engine. I just hear some clicks from the cluster when trying to connect to the module. I went to Audi dealer and they tried also to connect to the ECU but with same result - They state that the ecu is bad and needsto be replaced. Ok, so I bought an used ECU, put it on the car trying to recode it, but, when trying to connect to it I get the same message------ No response from controller -----same clicks from the cluster----the only difference is the immobilizer that blinks. Is it possible that the cluster is bad? Is it possible that the guy who had the car before changed the cluster and the keys but he didn't recode it with the ECU??
 
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Hello guys, I don't know if it is the right place to write but... My problem is that I cannot read the ecu via vagcom cableI have an A2 1.4 petrol from 2001 and I get an ''no response from controller'' every time I want to read the engine. I just hear some clicks from the cluster when trying to connect to the module. I went to Audi dealer and they tried also to connect to the ECU but with same result - They state that the ecu is bad and needsto be replaced. Ok, so I bought an used ECU, put it on the car trying to recode it, but, when trying to connect to it I get the same message------ No response from controller -----same clicks from the cluster----the only difference is the immobilizer that blinks. Is it possible that the cluster is bad? Is it possible that the guy who had the car before changed the cluster and the keys but he didn't recode it with the ECU??

Hi,

the ECU immobilisation is pared with the Cluster so if you change to an ECU from another car then the key symbol will flash indicated that the car cannot be started. This is the expected behavior.
The fact that the key flashes for the replacement ECU but presumably goes out after a few seconds with the original ECU is a good sign as it means that the ECU is working and communicating with the Cluster.

The diagnostics bus which your VAGCOM connects to is a different circuit to that used by the computers in the car to talk to each other. Its a "shared" bus which means that the diagnostics wires from all devices are connected together. A fault in one device will cause problems accessing others. for example I had a faulty steering wheel controller module in my car and this caused random "no response from controller" errors from the ECU.

Do you have an aftermarket Radio head unit in your car? If you do, a lot of aftermarket adapter leads mistakenly short the diagnostics bus wires in the radio connector to the battery positive causing the diagnostics bus to fail. If you do have an aftermarket Radio then this may be the problem:

http://www.ross-tech.com/vag-com/aftermarket-radio.html

regards

Andrew
 
Tnks from the quick reply. The car starts with no problem with the original ECU, I have no lights on the dash and I am able to connect to the rest of the modules. Is it normal to hear those clicks from the dashboard when trying to connect to the engine? I have an aftermarket radio, and yes, I read a lot about this problem. I have checked the connection and it seems that the pin pointed in the diagram is not there (pin 3) --it's missing. I have allready tried to read the engine module with the radio out of the car with same result. I will double check as now I know for sure that the ECU is Ok and the problem is somewhere else.
Best regards Madalina
 
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Tnks from the quick reply. The car starts with no problem with the original ECU, I have no lights on the dash and I am able to connect to the rest of the modules. Is it normal to hear those clicks from the dashboard when trying to connect to the engine? I have an aftermarket radio, and yes, I read a lot about this problem. I have checked the connection and it seems that the pin pointed in the diagram is not there (pin 3) --it's missing. I have allready tried to read the engine module with the radio out of the car with same result. I will double check as now I know for sure that the ECU is Ok and the problem is somewhere else.
Best regards Madalina

Hi,

clicking noises from the cluster are normal and not something to worry about.

regards

Andrew
 
My problem is that I cannot read the ecu via vagcom cableI have an A2 1.4 petrol from 2001 and I get an ''no response from controller'' every time I want to read the engine. I just hear some clicks from the cluster when trying to connect to the module. I went to Audi dealer and they tried also to connect to the ECU but with same result - They state that the ecu is bad and needsto be replaced.

Hi Madalina,

With your VAG-COM cable, open the options menu, look under protocol options. You should see the 'Start Baud' box; change this value to 9600. The usual symptoms of this needing to be done are slightly different, but as your car is running, it's worth a shot. There's more information here. :)

Many thanks,

Matt.
 
Thanks for help guys. I found the problem going backwards from the ECU harness and following the wires. I think the water went in at some point and compromised 2 wires. Simple fix by cutting the wires from the corresponding plug and made again the correct connection. Happy ending.
 

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I have the Airbag light on on the dash and my garage has advised swapping out the ECU for a refurbed one. Do any members offer advise or swap service ?

PS
I read with interest the earlier post

Just swapping the ECU is a 10min job as long as your old one is working, with programing.
And it's not really true that you need to re-program it ;) You can just remove the immobilizer chip from the old ECU and re-place the IMC on the new ECU “
But I don’t understand it ?
 
My car seems to having a similar frustrating issue.

Having a bit of a problem with my A2 this week it's a 2002 1.4 SE petrol and over a few weeks it became difficult to start. Then it took about 10-15 to start. Then once I got it started it dropped down before cutting out and required several revs of the throttle to keep it going. This was disagnosed as a coolant temperature sensor and once replaced it started on the button. The diagnostic test also threw up a fault for an EGR.

Then l took it out last week and it drove about 5 miles with no problem or lights on the cluster. Then when I came out of the supermarket to start it up it went lumpy and died as soon as I put it in gear and took my foot on the throttle, when it was running it sounded and smelt like it was running rich . The dashboard had several lights, the EPC,ABS plus the engine management light and on the digital display the Engine Fault detection light.

I have AA membership so their mechanic turned up and did a test, said the engine was running fine one minute, then lumpy the next. He said he thought there might be air getting in somewhere he sent me the diagnostic test and towed it to my local garage. This is the readout from the AA diagnostic attached

So the car was looked at and a new manifold ordered from Audi, this was fitted to the car and the mechanic took it out for a spin on two consecutive days and both times the car started perfectly and drove fine for a few miles before beginning it's lumpy routine and struggling to get past 5mph. The mechanic seems to think it might need an ECU but I'm stumped. The car appears to drive ok and then it's almost like when it gets up to temperature it just drops and won't accelerate past 1st gear/5mph

From reading I've come across everything from camshaft sensor to something connected to the EGR but to be honest I've no idea and the experienced mechanic doesn't seem to have found a solution either. It seems from reading that an ECU fault is unusual as surely if it wouldn't drive right from start up if it was the ECU.

Any help greatly appreciated
 

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My car seems to having a similar frustrating issue.

Are you getting misfires ? (the running lumpy bit when it warms up sounds familiar). Our 2002 1.4i was a bit rough when acquired and had a periodic trembly patch on a part throttle at around 1500-1700rpm but would run fine if you floored it. Last summer it became more and more erratic - engine light on, running on 3 cylinders, smell of fuel etc, but always some time after starting up fine. I had already replaced plugs and leads with new ones, throttle body and EGR were done the year before as the former was really dirty and the latter had failed, so I decided that the injectors might be worn, got a set fully refurbished and fitted those. Problem was still there. I eventually realised that the (original) coil pack on the end of the engine was really compromised - cracked casing, shrunken potting compound on the back etc. so this was replaced with a new Bosch one. Immediate transformation - smooth running, slightly better economy etc.

Worth noting that you can only really see if the coil pack is compromised by taking it off and looking at the back and underside - the top side that you can see in situ was unmarked. 3 allen key bolts to undo, easy to check.
 
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Having a bit of a problem with my A2 this week it's a 2002 1.4 SE petrol and over a few weeks it became difficult to start. Then it took about 10-15 to start.

Can you clarify whether you have the AUA engine or the BBY?
 
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