ECU Fault code? Internal Control Module Memory Error

[newsh]

What does this one mean? Engine was not running hence G28

VAG-COM Version: Release 311.2-N

Control Module Part Number: 895 907 404 BA
Component and/or Version: MOTOR MRC 1
Software Coding: 0261200484
Work Shop Code: 1267356560

2 Faults Found:
65535 - Internal Control Module Memory Error
00-00 - -

00513 - Engine Speed Sensor (G28)
03-00 - No Signal

[terrybullwon]

John i have this hth,

Possible Causes
Control Module housing leaky > Control Module wet
Wiring from/to Control Module faulty
Control Module faulty

Possible Solutions
Check/Clean Wiring from/to Control Module
Replace Control Module

[newsh]

Thanks James, so the Control Module is the ECU then, yes?

Maybe one of those wiring plugs on the bulkhead has water in it?

[terrybullwon]

Thanks James, so the Control Module is the ECU then, yes?

Maybe one of those wiring plugs on the bulkhead has water in it?

Did i read some where that your car was not running right at the track?

[newsh]

Did i read some where that your car was not running right at the track?

Yes, holding back, timing seems to retard, a bit like a misfire but not really bad, just feels a bit gutless, feels like it runs fine on small throttle openings but as soon as you ask a bit more from it it goes rough and flat. Boost seems ok, I'm pretty sure I don't have a leak.

[terrybullwon]

Yes, holding back, timing seems to retard, a bit like a misfire but not really bad, just feels a bit gutless, feels like it runs fine on small throttle openings but as soon as you ask a bit more from it it goes rough and flat. Boost seems ok, I'm pretty sure I don't have a leak.

I think it could be a vacume line in the ECU, the text i have here seems to point that way

[newsh]

I'm sure I'd hear that though, if it was leaking, I had the ECU apart a little while ago when this code first appeared, couldn't find anything wrong Need to do a pressure test I guess, but its tipping it down now and very dark out..
In the past, with even a small leak I will get the big lurch, cutting out behaviour.

I've just had a look at the plugs on the bulkhead, all clean and ok, although the clip is missing from one of them.. Gave them a squirt with de-oxit anyway, checked the ground wires on the manifold, all looks good.

[newsh]

Looking like it may be a ground problem.

http://www.s2forum.com/forum/search.php?searchid=477929

[newsh]

Quite a lot of previous experience, could be checksum error or ground problem or voltage problem. Nobody posted a fix though

[newsh]

As in one of the other threads about this code:

If I just switch on the ignition and pull the codes I get the fault come up, if I clear the codes, get no faults, and then switch off and on again the fault always reappears. If I start the engine, clear the faults and restart it doesn't reappear, stop the engine and switch back on but do not start, it reappears again.

[newsh]

This morning I started the car then cleared the codes. I then went for a drive giving it enough stick so after 1/2 hour I was getting it holding back and running rough. At times the car would make a droning noise at full throttle, like the exhaust was shaking/vibrating.
Got back pulled the codes while engine still running, no faults. It definitely seems this fault only appears when codes are pulled with engine not running. It may therefore be a red herring and unrelated to the poor running of the car.

[r1alex]

I have had this problem with an amd ecu, exactly the same symptoms as you, and as soon as I put the homefries loaner on I vagcomed it and nolonger had a65535 fault code so in my opinion it is a checksum error newish, hope that helps.

[newsh]

Ok, thanks for that Alex, you can see from the fault code printout who mapped the car, I'm reasonably sure it didn't do it when first mapped, I've never seen it as a blink code for example, I only recently got vagcom going, its a cheap lead off ebay, as soon as I ran it on the car I saw this code.

This afternoon I've had the whole inlet tract to bits pretty much, refitted the original 3B Samco MAF hose as the DV return points straight at the turbo inlet (the revised one points the return up towards the MAF which I don't like) With the new IC setup I don't need the revised hose now anyway. I also changed the DV for a spare forge one I had. This seems to have cured the off throttle surge I was getting.
I took the car for a run and all seemed well for a while then it started playing up again, this time I could hear a small hissing inside the car, the hose where it fits to the ECU is an original cotton braided piece and it had compressed to allow it to leak even with the clamp tightened up. I'd recently suspected this and trimmed the end of the hose so it clamped on a new bit but it had started leaking again.
I swapped 2 of the clips round to allow it to be tightened up more and took it for another spin, finally all now seems to be ok.
So, all a bit vague, I didn't hear the leak before at the track or on the way home of over the last 2 days, to be fair at the track we were wearing crash hats so wouldn't have heard it anyway, and I've been wearing a wooly hat while working on it, this time out I wasn't wearing the hat and the leak was quite obvious once I noticed it
Changing the DV may have helped too, the Bailey has been on there for about 3 yrs.
The Forge seems to be opening better.
The MAF hose is now the one the car was mapped with.
The occasional boost spikes of up to 2.2 Bar or higher have now gone. I'm pretty sure we saw nearly 2.5 Bar once on the track

[newsh]

Thinking about it, the boost spikes could have been because of the map sensor hose leak If the ECU was reading lower pressure than the actual boost it would try to raise the boost thereby pushing it over the nominal 1.9 Bar Its mapped to. Also with more actual boost than the ECU was reading the timing would not be correct and it would be pinging so the ecu would be sensing knock and richening the mixture and retarding the timing..

[newsh]

Conclusion
I don't know what the fault code is for or even if its relevant.

I do know that James is Terrybully clever though, cos he actually diagnosed my problem.
The leak was at the vac tube connection to the ECU, and not always leaking, dependant on how much boost and how it seated when going from vacuum to boost.

Thanks James

I think it could be a vacuum line in the ECU, the text i have here seems to point that way