Engine died twice...

[spikemoto]

My issue which seemed to only happen past 15psi turned out to just be spark plugs

[Lloyd]

Time for an update; The source of the electrical problem has been finally traced to the ECU. It was not the key fob, although the ignition barrel is undoubtedly well worn.

In summary we found that you could lightly 'tap' the ECU case and it would repeatedly cause either a misfire or (most frequently) immediate total engine shut-down.

Furthermore, we know the fault is not due to either of the chips or their sockets, both have been swapped out without improvement. We've also tried my ECU in Rich's car and it exhibited the same result. Main suspect at the moment is a broken wire in the ECU ribbon cable...

Car is now up and running and had been without fault or error code for some 800 miles. Big thanks to Rich (Hoffer76) for kindly supplying me with a spare ECU to run the chips and get the car moving, whilst we try to get my one fixed up.

[prj]

Don't forget to mention that it was not only the ECU.

Initially we could make the car stop every time by moving the wiring by the hall sensor.
The hall sensor was rewired and that problem was fixed.

The second problem seems to be either ribbon cable defect or cold joint in ECU, as it loses G4 signal.
I will try to trace it and fix it.

So it was two problems at the same time, which made it harder to diagnose it right away.

[Lloyd]

Yes, with the engine shutting off every now and again the ECU was storing a fault code suggesting there was something wrong with the Hall sensor. I duly changed the sensor sadly without improvement in the shutting off problem or fault code.

We then soldered up the connectors in the plug, still without improvement. Some weeks later I found that one of the pins in the plug was the wrong way around giving an intermittent connection.

Whilst there were two problems, the original fault was with the ECU. I suspect it may even be possible that the Hall fault code was a false flag caused by the intermittent ECU fault? I mean, there was nothing really found to be wrong with the Hall. Whilst the car did shut down two or three times whilst moving the injector loom, it was far far from being repeatable. On the other hand, tapping the ECU case is 100% repeatable.

BTW: Thanks for offering to have a look at my ECU Dmitri, much appreciated

I too am looking forward to your next UK visit to get the tune finalised.

[prj]

Whilst there were two problems, the original fault was with the ECU. I suspect it may even be possible that the Hall fault code was a false flag caused by the intermittent ECU fault?

Well, when I was over there trying to diagnose it, we definitely could make the car stop via wiggling the Hall sensor wire, so that's why I thought it was the problem.

ECU was definitely giving a problem too though.
Just have to find where the broken trace/cold joint is. I am afraid that won't be very easy.
The only thing I am happy about is that vibration causes it, so it must be just a bad connection somewhere, rather than a bad chip.

[Ross]

Glad to hear this is solved Lloyd

Amazing how these faults can be so ****** awkward to find - I mean, who'd ever suggest tapping the ECU

If it's a bad connection I bet Dmitri can solder it - he soldered replacement pins onto by broken fuelling chip at 3am for my ECU

[prj]

he soldered replacement pins onto by broken fuelling chip at 3am for my ECU

Good times

[Lloyd]

I mean, who'd ever suggest tapping the ECU

Yeah, it's was a lucky find to be honest.

Just so good to have it up and running again

[Ross]

You're on the latest K26/7 from Hoffer right? Once you've got it up and running (hopefully Andy too) I think it's time for a dyno head-to-head at MRC

[Lloyd]

You're on the latest K26/7 from Hoffer right? Once you've got it up and running (hopefully Andy too) I think it's time for a dyno head-to-head at MRC

Ha! Now you're talking.... :mischeif:

You've got uprated rods though so not quite a level playing field.
Will be great to compare the different set-ups & results.

I'm hoping to arrange Dmitri's next visit to include a visit to the hub dyno at Torque Developments to finalise my tune. (TDI) https://www.tdi-plc.com/index.php?pge=C_dynocam They've just bored out their hub adaptors to fit the RS2. Hire out their dyno for a couple of hours. This bit of kit can hold a car at any desired RPM at full power. Awesome for fine tuning. Complete control!

Anyone else up for mapping on the dyno?

[Avantus]

Good news this Lloyd! What a long search that was.

And would be cool to share/compare all our K26/27 results

[ccl68]

My RS2 seem to have the same problem of late.
It will cut out intermittently, either on acceleration or deceleration, cruising at speed or in slow traffic.
Having stumble upon this thread, I hope to be able to sort out this problem.
I will look into the hall sensor wiring & the ECU connectors.

Thanks to all that have posted their experience.

[prj]

First thing is to pull codes from the ECU. It can always be a tired fuel pump as well etc.

[ccl68]

yes, need to do the whole set up cos older VAG cars are rare here... sigh...

[bluequattro]

Just read this post!
I m not getting codes but symptoms were the same
Gonna try tapping ecu
Also thinking there may be a water leak from when car was standing that may have got into the wiring