Audi S4 no start

[Pirvu Eugen]

hello guys!
I have an friend with an S4 AAN engine which sometimes it stops sudenly and is not starting animore until you let her cool a little bit. No error codes are shown when I keep her cranking over when is not starting. Which are the no start conditions which are not showing codes? I have checked the hall sender, timing, timing sensors. Sometimes starting, sometimes not.
Please

[Greg_S]

Have you checked the MFTS?

[Pirvu Eugen]

Sorry! Multi (malfunction) temp sensor?
No didint checked. What is with that?

[LHD_Kid]

Multifunction Temp Sender,
its the larger of the two sensors in the underside of the water manifold....

Chris

[Pirvu Eugen]

Sorry! I know what is and where is it, but I dont know how can afect that sensor the startup of an aan engine. I understand that the aan ecu is not using the signal from this one for reducing boost for example like in 3b engine.
I am wrong?
How can afect MFTS the starting?

Thank You!
Eugen

[UrS4boy]

Sorry! I know what is and where is it, but I dont know how can afect that sensor the startup of an aan engine. I understand that the aan ecu is not using the signal from this one for reducing boost for example like in 3b engine.
I am wrong?
How can afect MFTS the starting?

Thank You!
Eugen

You are correct. For a AAN (or ABY) the MFTS has nothing to do with the control of anything, running or starting. See the link:

http://forums.audiworld.com/s4s6/msgs/148742.phtml

IF you are 100% sure its not the cam position sensor hall sender (blink code 2113), then I would have to think its the fuel pump about to totally die. Follow this link for fuel pump testing:

http://forums.audiworld.com/s4s6/msgs/89799.phtml

I have a fuel pump replacement procedure write-up but the host link is down.

Dave F.

[Pirvu Eugen]

And still, on S2 central site the ABY engine ecu on pin 46 has an input from the MFTS.
Greg knows something!!! maibe the mfts is not use to cut off boost, is use to shut of the engine. I dont know.

All the best!
Eugen

[Pirvu Eugen]

Is possible that the hall sender to be bad without showing any codes?