Audi A3 2004 2.0l tdi sport

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Audi A3 2004 2.0l tdi sport

Postby readyrangers » Sun Apr 07, 2013 10:22 am

Hi I have been having problems with my car for the last six months, it keeps giving implausible signal on injectors. I have replaced the wiring harness under the rocker cover three times and changed the main harness also, the last twice the one under the rocker cover had worn the cable and exposed the bare wire caused by vibration. I had replaced all the injectors with reconditioned ones, i now have four brand new ones in. The ecu was sent away to be tested, I was told it was faulty they tried to repair it but ended up needing a replacement one. I sent it away again to get it tested it came back as being fine, once I plugged it into the car I went from having two injector problems to having four. I fitted a new tandem pump as it was pulling oil from the engine into my diesel, my tank was flushed out the filter was cleaned and the lines were cleaned out also a new filter.
I had a diagnostics boy doing the last lot of work on it for me who had been using picoscope but he is away on holiday now for a week, I have a couple of files he sent me to send to the company that done the ecu but they have not replied to my email yet.
The car starts and runs perfectly till it gets to forty degrees gives a stutter for around ten seconds then ticks over fine again, when it gives the stutter it throws up the four fault codes. Can anybody help me or have any ideas what could be causing this does it sound like an ecu problem?

I think this is what it shows when it is cold but the faults are not cleared.
The two graphs he sent me are in the attachment.

The 4 fault codes are listed below.
4 Faults Found:
17671 - PD Unit Injector: Cylinder 2 (N241)
P1263 - 000 - Implausible Signal
Freeze Frame:
RPM: 1806 /min
Torque: 74.0 Nm
Speed: 47.0 km/h
Load: 21.6 %
Voltage: 14.29 V
Inj. Quantity: -0.49 mg/str
Temperature: 31.5°C
(no units): 16.0

17668 - PD Unit Injector: Cylinder 1 (N240)
P1260 - 000 - Implausible Signal
Freeze Frame:
RPM: 1806 /min
Torque: 74.0 Nm
Speed: 47.0 km/h
Load: 21.6 %
Voltage: 14.29 V
Inj. Quantity: -0.21 mg/str
Temperature: 31.5°C
(no units): 16.0

17677 - PD Unit Injector: Cylinder 4 (N243)
P1269 - 000 - Implausible Signal
Freeze Frame:
RPM: 1785 /min
Torque: 76.0 Nm
Speed: 46.0 km/h
Load: 21.6 %
Voltage: 14.29 V
Inj. Quantity: -1.20 mg/str
Temperature: 31.5°C
(no units): 16.0

17674 - PD Unit Injector: Cylinder 3 (N242)
P1266 - 000 - Implausible Signal
Freeze Frame:
RPM: 1701 /min
Torque: 80.0 Nm
Speed: 46.0 km/h
Load: 21.6 %
Voltage: 14.29 V
Inj. Quantity: 1.95 mg/str
Temperature: 31.5°C
(no units): 16.0

I am hoping somebody has had a similar fault as mine, I have tried loads of forums but cant get to the bottom of this.
Thank you.
Shaun
Attachments
pd injector example.psdata
(181.87 KiB) Downloaded 280 times
audi a3 cyl 4 after.psdata
(145.83 KiB) Downloaded 263 times
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Re: Audi A3 2004 2.0l tdi sport

Postby readyrangers » Mon Apr 08, 2013 9:24 am

Hi again, I forgot to add what my diagnostic's boy told me before he went away.


What is missing is the hold current and when seen over a longer time scale the beginning of injection period is all over the place, these are both controlled by the ECU with beginning of injection calculated from the hold current of the previous injection.


The hold current is missing when the car is cold as well but does not trigger the fault codes till the coolant temperature passes 40 degrees.
It will then occasionally stutter and reduce injection quantity to almost 0 for 10 to 15 seconds then idle stable again.

Thank you.
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Re: Audi A3 2004 2.0l tdi sport

Postby Liteace » Mon Apr 08, 2013 1:04 pm

How many mile\Klms has the vehicle done ?
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Re: Audi A3 2004 2.0l tdi sport

Postby readyrangers » Mon Apr 08, 2013 3:17 pm

Hi it has done 89000.
Thanks
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Re: Audi A3 2004 2.0l tdi sport

Postby KimAndersen » Tue Apr 09, 2013 9:37 am

Hi

First i want to say - that i have no solution to your problem. It seems like it is temperature related and that could mean there is something wrong with your coolant temperature or your fuel temperature sender (G81). As you have done a lot off replaceing parts you had to dig deeper to find this fault.

One thing i would recommend when dealing with a VAG car is a diagnostic program called VCDS as its so much better - than those simple OBD software you can get.

Your diagnostic boy should know this program.

To diagnose a problem car is a difficult task - even if you has all the right equipment you wouldn´t be able to diagnose the car, if you cant interpretate the result you get from different diagnostic test done on the car.

What you need to diagnose this problem is a good fundemental understanding of how the system works and operate. You have have found there is a problem with PD injectors by using the Picoscope and that is a first good step in the process of diagnosing this problem.

But how are the PD injectors controlled - what others inputs are needed for the PD injectors to inject the correct amount of fuel ?

All I´m trying to say is - that sometimes you has to think out off the box to get the full picture.

I know this isnt much help, but it is a start. :wink:

Regards
Kim
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Re: Audi A3 2004 2.0l tdi sport

Postby readyrangers » Tue Apr 09, 2013 10:26 am

Hi Kim, thank you for taking the time to reply to me.
As far as I know it was vcds he was using while testing it, I had asked everybody that has tried to sort it if there was a sensor that could be causing this, everybody told me if it was a sensor it would show up in diagnostics.
I have even had it in Audi, they had it for five hours and could not work out what was causing the problem, they told me they could sort it but could give me no idea of time and price. I have now got a friend who works at an independent Audi specialist to speak to the owner to see if he will look at it for me, I will come back on and report anything he finds if he will look at it.
Thanks Shaun
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Re: Audi A3 2004 2.0l tdi sport

Postby mteste03 » Tue Apr 09, 2013 6:37 pm

Hi,

A sensor may not be giving the correct output but not log a fault code becuase it is still operating within the defined parmaters that the ECU uses. Looking at live data is important; as relaying on codes does not give the full picture.

Matt
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Re: Audi A3 2004 2.0l tdi sport

Postby readyrangers » Tue Apr 09, 2013 9:02 pm

Hi Matt, thanks for that. I am booked in for Wednesday afternoon at the specialist, hopefully he can help me out. Were the graphs I added to the post any use at all? with not being a mechanic I am none the wiser what they mean.
I took the car out tonight for the first time since I got it back from having the fuel lines cleaned the new injectors, the wiring harness and the turbo veins cleaned. I have to admit when cold it went a lot better than it has for a long time, even when hot now it takes full revs where before it only went to around 3000 rpm. Although it takes full revs once it warms up now it has a severe lack of power.
Thank you.
Shaun
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Re: Audi A3 2004 2.0l tdi sport

Postby readyrangers » Wed Apr 24, 2013 9:35 pm

Hi just a wee update. It turns out that all this time the replacement ECU I got was faulty, it was a fault that does not show up on testing stations.
Thanks
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