Audi S2/RS2 not starting

[s0_big]

http://s2-audi.co.uk/workshop/schema..._aby/page5.png - pin 37 is switched 12v at the ecu for the injectors

Ok, then I have checked that. I have 12V with ignition on and also while cranking at the injectors.

[mllen89]

measure if you have 12v between pin 4/6, 5/6 in the maf connector ? with it still mounted, have you tried to start it wiith the maf unpluged ?

[s0_big]

measure if you have 12v between pin 4/6, 5/6 in the maf connector ? with it still mounted, have you tried to start it wiith the maf unpluged ?

Ok, Will check that. I have 12V to the maf that i have measured. I have tried but no start.

[GT500]

Even though you have fuel at the rail and it is flowing through if they are on the wrong way around you won’t get the right pressure. Get a gauge on it. Pressure has to be right. You can use a tyre gauge if you have to.

[andersg]

You can easily bypass the alarm (inside the central locking box) if you make a jumper cable between switched and permanent 12v into the ECU. It caused me a lot of headache.

[twoqu]

Another known issue is the actual injector connectors themselves. Would be a bit unlucky to have all five not making contact but worthwhile eliminating them.
They crumble inside so it might not be obvious.

[s0_big]

You can easily bypass the alarm (inside the central locking box) if you make a jumper cable between switched and permanent 12v into the ECU. It caused me a lot of headache.

If it is an alarm issue, what's the symptoms then?

[Vauhtiveikko]

Make sure that also this plug is as it should...

[s0_big]

Another known issue is the actual injector connectors themselves. Would be a bit unlucky to have all five not making contact but worthwhile eliminating them.
They crumble inside so it might not be obvious.

I have measured both 12v+ and minus- on all connectors. I will continue tomorrow with the fault finding.
one thing that popped up my head is that I removed the hood, there was 2 cables that I had to cut to get it off. Could those two cables make these kinds of problems you think? Maybe some earth point thats interrupted? First thing tomorrow I will bolt the hood back on and these two cables to make sure thats not my fault.. Thanks for all the help and replies so far

[Tractor Dave]

I think the wires you cut are to the heated washer jets or the under bonnet light. Shouldn't make any difference but make sure its not shorting out.

[Tractor Dave]

I had non starting issues. Took me weeks to find what the problem was, slowly eliminating one possible cause after another. You may have already read in my thread but it was found to be the top cambelt pulley key which had sheared, allowing the timing to slip enough for the engine not to start. I still had spark, fuel, compression, just at the wrong time! The key sheared because during the engine re build it wasn't torqued up correctly! The only way to see it was to remove the rocker cover as the timing marks slipped to a position where they lined up again.

[twoqu]

Didn't get a answer to your earth/ground readings. On pin 30 you have said its 18M Ohms? Was that a mistake?

[s0_big]

Didn't get a answer to your earth/ground readings. On pin 30 you have said its 18M Ohms? Was that a mistake?

No thats correct. But I have ground at the sensors that are connected to pin 30 when I put the ECU-connector to the motronic. Read some were that the ground to pin 30/48 is taken from either 10/14/19/24 through the ECU and out to pin 30/48. Correct me if I'm wrong. Then thats maybe my problem.

[s0_big]

I had non starting issues. Took me weeks to find what the problem was, slowly eliminating one possible cause after another. You may have already read in my thread but it was found to be the top cambelt pulley key which had sheared, allowing the timing to slip enough for the engine not to start. I still had spark, fuel, compression, just at the wrong time! The key sheared because during the engine re build it wasn't torqued up correctly! The only way to see it was to remove the rocker cover as the timing marks slipped to a position where they lined up again.

Yeah, i have read your thread

[twoqu]

No thats correct. But I have ground at the sensors that are connected to pin 30 when I put the ECU-connector to the motronic. Read some were that the ground to pin 30/48 is taken from either 10/14/19/24 through the ECU and out to pin 30/48. Correct me if I'm wrong. Then thats maybe my problem.

But I thought you said the readings were with the ecu connector off. So shouldn't that be directly to ground and 0 ohms?
Can't remember if pin 30 is the main ecu earth if you see what I mean. The one that is attached to the A pillar rather than the ones on engine.
Will have a think about it.