RS2 Wont Start

[dave944s]

Hi People

RS2 is parked up for the winter and I start and run it every other week if I remember, went in to run it and it won't start, (was run three weeks ago) engine turns over, I can hear the fuel pump run then stop (presume it is pressurising), took the spark plugs out and they are dry, presume not getting fuel (1/4 tank showing) but just incase the fuel gauge is not working I put 2 gallon in to make sure, tried again still not starting and the plugs are still dry, is there a relay specific to the injectors that would cause this or am I missing something, would like some help as I am at a loss, I am not a mechanic and don't propose to be, so all help appreciated.

Dave S

[UrS4boy]

If the battery is too flat to get the engine spinning at 13+ RPM, the ECU will NOT energize the fuel pump relay (not sure why you are hearing the fuel pump with key on). No fuel pump relay, no start. So make sure the battery is fully charged before attempting a re-start.

I did a post on starting issues (link below). It says its for AANs but it applies equally well to ABYs and ADUs. Have a read.

http://www.s2forum.com/forum/showthr...ential+reasons

[AndyP]

Have a read of this too:-

http://www.s2forum.com/forum/showthread.php?t=49771

[dave944s]

Sorry didn't say, first thing I did was fully charge the battery, I have also checked if the injector is getting power and it is getting power, is there any way the fuel would be not getting through (evan though the fuel pump seems to be working ?

If the battery is too flat to get the engine spinning at 13+ RPM, the ECU will NOT energize the fuel pump relay (not sure why you are hearing the fuel pump with key on). No fuel pump relay, no start. So make sure the battery is fully charged before attempting a re-start.

I did a post on starting issues (link below). It says its for AANs but it applies equally well to ABYs and ADUs. Have a read.

http://www.s2forum.com/forum/showthr...ential+reasons

[dave944s]

Thanks checked the thread you mentioned, with the return pipe off I am getting fuel through into a jar when cranking the engine, although the thread mentions G4 and G40 sensors I couldn't see how to check for a spark, so is it correct to suspect it is an electrical problem, is there any way of bridging out the sensors to see which is the problem.

If the battery is too flat to get the engine spinning at 13+ RPM, the ECU will NOT energize the fuel pump relay (not sure why you are hearing the fuel pump with key on). No fuel pump relay, no start. So make sure the battery is fully charged before attempting a re-start.

I did a post on starting issues (link below). It says its for AANs but it applies equally well to ABYs and ADUs. Have a read.

http://www.s2forum.com/forum/showthr...ential+reasons

[UrS4boy]

Thanks checked the thread you mentioned, with the return pipe off I am getting fuel through into a jar when cranking the engine, although the thread mentions G4 and G40 sensors I couldn't see how to check for a spark, so is it correct to suspect it is an electrical problem, is there any way of bridging out the sensors to see which is the problem.

If you go back to that post, wherever there is underlined text, it is actually a hyperlink to more info about that device, i.e. the G40 or the G4. In the case of the G40, there is info on how you can use a LED to check that your G40 is functioning or not. No G40 (or G4) at the time of starting = no spark.

Checking spark can be done as suggested in this Missing and Hesitation Diagnostic post:

http://forums.quattroworld.com/s4s6/msgs/22611.phtml

[chez]

Check the neg side of the spark plug connector to see if you are getting a pulsed neg when cranking.

[dave944s]

Thanks for all the help, I am going to order a G40 sensor, but before I do, would a fault code show that the sensor has failed, if it would, what fault code would it show, I can't get a vag com but I can borrow a Vgate Scan tool which (I hope) would give the fault code if its there, any thoughts

[UrS4boy]

Thanks for all the help, I am going to order a G40 sensor, but before I do, would a fault code show that the sensor has failed, if it would, what fault code would it show, I can't get a vag com but I can borrow a Vgate Scan tool which (I hope) would give the fault code if its there, any thoughts

•2113 (Blink Fault Code), 00515 VAG1551/2 Fault Code Number
(G40) Hall sensor in distributor (3B, early AAN engines) or camshaft position Hall Effect sensor later S4/S6 AAN engine). Distributor alignment, faulty sender, Mis-located sensor & distributor, Cam timing possibly incorrect on AAN engine, Check lower Crankshaft Gear keyway Symptom: Engine will not start, power loss, check engine light may come on during driving above certain RPM

As suggested in my G40 post that I linked you to, you can set up an LED to show you that the G40 CPS is working properly by connecting an LED between Pins 1/3 and 2/3 (while still connected to the harness).

More info here (also hyperlinked out of my G40 post):

http://www.efiexpress.com/catalog/ar...articles_id=11

[dave944s]

Thanks UrS4Boy

Two fault code present, this one,

00515 - 30 Fault code G40 Hall Sensor

Static - open/short

Circuit to positive

And this one,

00513-003

Engine speed sensor G28

Static no Signal

is it unusual that both sensors go at the same time, or is it because G40 has gone that the ECU thinks the G28 has also gone, or is there another reason ?

[Val]

G28 fault will go away after you start the engine.
That's normal because of dinosaur age ECU.

[hermanio]

replace g40

[dave944s]

G28 fault will go away after you start the engine.
That's normal because of dinosaur age ECU.

Thanks for that, next question, where is the best place to source a G40 sensor, or is this one part I just have to buy from my local Audi Dealer.

[UrS4boy]

Thanks UrS4Boy Two fault code present, this one,
00515 - 30 Fault code G40 Hall Sensor Static - open/short Circuit to positive

Well at least you know that the issue is the G40. Have a read on this (one of the links that was corrupted (somehow) in my non-start diagnostics post:

http://forums.quattroworld.com/s4s6/msgs/22580.phtml

Check the connector to make sure that the male and female pins are intact and connecting properly. Sometimes the connectors crumble.

In the link there is mention of being able to buy just the Hall Sender from EFI Express. Someone here just bought a bunch I think from someone in Europe so that should be a possibility.

In the link above, there is a link to this DIY that does not require complete front engine teardown, at least not for a C4 UrS AAN.

http://picasaweb.google.com/persing/...orReplacement#

HTH

Dave F.

[dave944s]

Hi all

Has anyone got a photo of the camshaft tool, I was thinking of making one if simple enough, thanks in advance.