hall sender trouble...

[archiboy24]

Hey guys,

Got back to the garage today and pulled the fault codes and cycled the output tests. The good news is the output tests were fine and there was only one fault code, 2113. The bad news is, 2113 is the hall sender, which has to be one of the most difficult things to get at, let alone diagnose what's wrong with it! It could be anything from a faulty Hall Sender or distributor in need of adjustment(fairly easy fix); a problem with the engine speed sender and/or reference pin (much more difficult); wiring (hard to believe since this is one area of the harness that's plug and play - no splicing); or the ECU (reeeally hope not, otherwise big $$$) Bentley says I need to remove a whole lot of stuff to expose the distributor. I really don't feel like doing this, considering it was all just put back together! I almost feel like towing it to the dealership, but no one has ever seen this engine in canada!
Anyway, this is the reason why it's not starting. I was wondering if anyone else has ever encountered this fault code and what the solution was. I'm trying to find out if one problem is more common than the other. I also don't have the electrical testing equipment that the bentley mentions (all I have is a digital multimeter), so if there are alternate test methods out there, I'd love to know!

Anyway, your help is appreciated!

Ben

[Josh-stateside]

I guess I am listing ideas here too:

Firing order
12453


Hall Effect Sensor (G40)

On the 3B engine, the hall effect sensor (G40) is located in the distributor. The signal provided by G40 is used by the ECU to :

Determine the ignition firing point for cylinder #1 when the engine is first cranked
Determine fuel injection timing and sequencing
Create a reference point for signals from knock sensors G61 & G66
If G40 fails, the engine cannot be restarted (as the ECU needs a reference firing point). However, if G40 fails while the engine is running, it will continue to run by deriving the firing points from signals received from G4 and G28. In addition, the ECU will retard the ignition by 6 degrees as a safety measure.


G4 is located on the left side of the engine near the flywheel. It is mounted alongside the crankshaft speed sensor (G28) and care must be taken not to confuse the wiring of these two sensors as they are identical in design.

If G4 fails, the engine cannot be restarted but if G4 fails whilst the engine is running then it will continue to run by making the fair assumption that the flywheel reference pin has not moved since the engine started !


Hypothetical thought:

you have the wires backwards on the engine for the reference sensor and speed sensor.


Interlectual smartness at my max with out seeing anything in person.

Check it out.

Cheers
Josh

[Vagsport]

I'm with Josh on this one. To determine easily if it's the Hall Sender, try tow starting the car. If it is, the car should run, if the Crank Reference Sensor / Firing Point Sender is at fault, the car should also run if tow started.

HTH

Siena

[Pisobiker]

My contribution as follows:

If for any reason the distributor isn't in the right postition (correct phase with TDC and sensor on flywheel) even of a very small amount, ECU wont spark ignition and will also not run injectors. AUDI service should have a sort of template to fit it the right postition.
Try to mesure voltage of one injector, whitout unplugging it, from the back of its connector, and have a friend turn ignition key while you read the tester. If no voltage detected and if you don't have access on the right AUDI tool for positioning the distributor, try making several starting attempts advancing and/or retarding the distributor of few degrees at the time around the point at which position should be correct.
If this is the cause, once you'll find the correct position, engine should start.

Marco

[Mihnea]

Ben,


It could be that the distributor gear is broken on your engine! If such a thing happens, you'll get the hall sender fault code, I've BTDT too.

Otherwise check its adjustment, the fault code means it's out of its range actually and it has to be adjusted very precisely, otherwise you either don't have boost or it doesn't start...


Cheers,

Mihnea

[archiboy24]

Originally posted by Mihnea
Ben,


It could be that the distributor gear is broken on your engine! If such a thing happens, you'll get the hall sender fault code, I've BTDT too.

Cheers,

Mihnea

Mihnea, it's a brass gear and it should be perfectly intact, as I just put the engine back together!

[archiboy24]

Originally posted by Josh-stateside
I guess I am listing ideas here too:

Hypothetical thought:

you have the wires backwards on the engine for the reference sensor and speed sensor.

Cheers
Josh

Josh, the connectors at the firewall for the ref. sensor and speed sensor are color coded to avoid this exact thing. I checked contiuity between the connectors for G4 and everything is fine. One of my other theories is that I installed the CQ flywheel without checking the clearances between the sensors and the flywheel teeth and reference pins. Since I just reinstalled the sensors that came with the 3B as is, maybe they aren't relating properly to the reference pins. Of course the teeth on the 200 and CQ flywheels are the same, so maybe it's just the reference sender I need to check.

[Mihnea]

Ben, are you absolutely positive you have installed the distributor properly? It needs to be aligned within a very small "window" otherwise it doesn't work. Anyway, the fault code means that for the ECU, the output signal of the hall sender doesn't correspond with what it's supposed to be seeing compared to the crank reference sensor (i.e. the hall signal has to happen at exactly 62 degrees BTDC)...

Keep us posted!

Mihnea

[archiboy24]

Originally posted by Mihnea
Ben, are you absolutely positive you have installed the distributor properly?

Keep us posted!

Mihnea

Well since the distributor was never removed, I can't see how it got misaligned. I only replaced the cap and rotor while the dist. was still attached to the head. My only thought is that it's 180 degrees out. But when the crank is at TDC, so are the cams. My Q is, does the dist. rotate once for every two cam shaft revs?

[A6 AVANT]

Double check the plug is on the Dizzy fully. I did a head gasket on a 3B a few weeks ago and it wouldn't run but the multi plug on the dizzy seemed on but wasn't. I had to push in the retaining clip and then push the plug fully home and then she fired up straight the way! Definitely worth a check! Good luck

[archiboy24]

Thanks, I'll try that!

[Vagsport]

There is only one reference pin on the flywheel. There may be two other pins on the clutch side, but these are for digital test equipment and nothing to do with the running of the engine. What flywheel did you use? I presume your transmission is 5 speed. These are all compatible:

RR (Ur quattro 20V), 3B (5 speed S2), WR (Ur quattro 10V > 87), MB (Ur quattro 10V 87 >), MC (100 turbo), KG (200 turbo > '87), 1B (200 turbo 190PS 88 >), 2B (200 turbo 200PS 88 >). NM (Type 89. 90 /Coupe) 7A (Type 89. 90 / Coupe).

These flywheels ALL have the reference pins in the SAME position in relation to the offset bolt holes. Make sure the pin is not broken, I don't know if you've had it running already, but these are things to look out for. I noticed something else in your comment:

""One of my other theories is that I installed the CQ flywheel without checking the clearances between the sensors and the flywheel teeth and reference pins."

If that is a Coupe quattro flywheel as I understand it, it won't have a reference pin (except it's a NM / 7A item)

Siena

[Mihnea]

@Siena: it's an US CQ, in the US they didn't get anything else but the 7A in their CQs, lucky ********

[Vagsport]

Ah. I see Mihnea. Still, us in Europe were even luckier to get the S2 and RS2 in our cars!

Siena