Intermittent power loss

[predding]

The little black thing, 38/01, is the visible part of the hall sensor. When the window in the thing you call the tuna can passes it delivers the camshaft position to the ECU.

That marker is fixed isnt it ie it cannot be moved by accident if touched...?

[newsh]

That marker is fixed isnt it ie it cannot be moved by accident if touched...?

No it can't be moved

[newsh]

That marker is fixed isnt it ie it cannot be moved by accident if touched...?

Which marker? The dash on the rotor? The rotor is fixed to the shaft which is geared to the cam, the gear on the end of the dizzy shaft can strip, some were plastic, a replacement metal gear is available. This would certainly cause a no-start but it would be obvious if you checked the timing marks.
IE as suggested before, Zero mark on flywheel aligned in bell housing window and marks in dizzy. If dizzy marks don't line up and you haven't moved anything then take the cam cover off and check the camshaft marks. If the camshaft marks and flywheel mark are aligned and the dizzy is not then pull the dizzy and check the worm gear.

[predding]

Cheers everyone. So yesterday I connected the test wires/bulb and switch to the Blue/Black/Brown ports of the OBD - double checking my conns according to the diagram from SJM. Tirned on ignition, lamp came on consistently - no flashing, activated switch (jumper) to off position, lamp stayed on. Reversed wire to bulb still the same. Disconnected all wires to try again and now nothing no bulb illumination or anything. Have triple check my conns and all good. I am convinced this car is possessed. WTF is going on...

[newsh]

Cheers everyone. So yesterday I connected the test wires/bulb and switch to the Blue/Black/Brown ports of the OBD - double checking my conns according to the diagram from SJM. Tirned on ignition, lamp came on consistently - no flashing, activated switch (jumper) to off position, lamp stayed on. Reversed wire to bulb still the same. Disconnected all wires to try again and now nothing no bulb illumination or anything. Have triple check my conns and all good. I am convinced this car is possessed. WTF is going on...

There's a fuse on the OBD 12v line, probably popped it.

[predding]

OK thanks - will check

** Update ** Spot on John - Fuse #21 Diagnostics 10A blown. Poss cause my unsealed connector blades into the ports had touched. Remedied now
Cheers

[predding]

So - with connectors insulated, reconnected and double checked, bulb lights constantly and removing the jumper wire makes no diff ie there is a constant feed from the 12v to the ECU Pin 55 - all connected as per here http://www.sjmautotechnik.com/troubl...20v.html#fault

I have had this blinking code working before some years ago so I know it works but now something looks odd with the ECU

Comments welcome. Thanks

** Update **

Managed to get the ignition on / jumper wire sequence activated after turning over the engine a few times on the starter

Reading the code it just provides 4444 which I believe is no fault codes stored

The odd thing though is that the engine 'fired' very slightly on a couple of cylinders for 2-3 seconds...so once again no idea what is going on

[predding]

1 year on and massive update for this thread...

Took car to local garage as I ran out of energy/mojo, the owner is into newtimer classics so has alot of empathy with taking care on older cars (he owns a mint 93 Integrale). I minimized the work requested as I just couldnt get the car to start so he did timing belt (he said it had slipped one tooth - God knows how), follower and new NOS Bosch distributor I sourced from Audi Tradition. He did a good job albeit I made sure he got the correct pulley locking tool from the local Audi dealer they had in their store who he knew well - dont think he would if I hadnt mentioned it.

So the car now runs but we are back to the original problem ie hesitates under load and runs rich on idle - I took it for a 60km run and then the temp gauge started to rise and fall erratically again - I have flushed out the system at least 4 times, cleaned all hoses with a bottle brush etc and soaked the system in 50/50 white vinegar and water to remove as much **** as possible and left flush in there for weeks to soak it all out. It runs pretty clear now with a hose gently connected

I filled it with only water before the run so maybe this caused the erratic temp gauge operation. On opening the bonnet on return the rad fan was running so that was good, and dropping in an out as it should, but there was a boiling water sound from the engine like it was boiling away like a kettle

NB! - One observation - I again tested the new thermostat in boiling water and it opened correctly but I have since noted in Seal/SJM that the thermostat should be fitted with the metal braces aligned in a vertical north south direction. I hadnt done this and will be doing on re-assembly though I studied the tstat hard and couldnt see how this made a difference. I also noted a tiny arrow on the tstat rim so if the brace is vertical, the arrow points to either the front or the rear of the engine depending on orientation - anyone else come across this?

I am now going back to square 1 now that the engine runs. So I have:

Bought new Coolant switch MFTS* (again)
New G62 thermo switch for rear of head (yet to be fitted)
New Turbo pump after run thermo sensor (old one out new one to be fitted)*
New Lambda Sensor (which I didnt replace) - just awaiting the special socket with cutaway to get the old one out. Forum comments and Seal Ltd suggest these should be replaced at 60k miles anyway

Thanks to FlatOut90 (Rob) who has been a great sounding board I have also located the Idle Stabilisation Valve and am just about to take it out and clean it all

I have also ordered a new Fuel Pump Filter as the last one was changed in 2011 so I want to ensure its not gunged up with old fuel gunge etc having stood for so long

And finally
At the suggestion of the garage, to check the head gasket, I have ordered a compression test kit to make sure as reading the symptoms on quattroworld, Seal and here, it mentions high fuel consumption and not pulling under load/misfire. (the LED instant fuel readout gauge was at 12,5 at best l/100km when it should be down at 8-9 l/100km

*Now - My one big question is:

I have tried to test both the MFTS and the After Run Thermo switch with a multimeter across the spade terminals while holding the sensor end in a shallow pan of bubbling boiling water. There is NO connectivity at all - the switch should activate around 87-110 degC so surely this would be enough (I even held one close to the blue gas flame - nothing)

I tested my MM with a 1500 ohm resistor and it was all good

So what is going on ie how do you test these sensors as I am baffled

I am just plodding through it all by process to at least get the cooling working again so I can re-focuss on the misfire.

Thanks for reading - all comments welcome -
Regards
Paul