AAN Engine transplant into VW T3 Transporter

[RS2]

Update...

With an LED wired between pin 2 and 3, the LED is lit most of the time within cranking. Only going off once every revolution of the camshaft.

Is this correct?

I've read about making up the LED tool so that you can see what's going on but no one has actually stated what it should do... Unless I've missed a bit which is staring me in the face... Which is highly likely

Also checked the crank-cam timing. It's spot on.

MG

[UrS4boy]

Update... With an LED wired between pin 2 and 3, the LED is lit most of the time within cranking. Only going off once every revolution of the camshaft. Is this correct? MG

Hmm...something happening only once per cam revolution is correct. I thought it was you get a blink once rather than a shutting off once per cam revolution (it might just be you have the LED legs swapped). But once something would seem to say the hall sender is functioning.

Can you try the diesel starting fluid sprayed into open throttle body during a cranking/starting attempt. If the engine catches better than it has before, it will point to the fuel supply system. If it doesn't catch then we are looking at spark.

[porkkis]

You simply thought a bit wrong. That's the way it should work.

[RS2]

You simply thought a bit wrong. That's the way it should work.

Great, thank-you for the clarification.

I know that I've got a spark and me activating the injectors is the same as spraying easy start into the throttle body.

I think it's time to try another ECU or try mine on another car.

MG

[porkkis]

So it does absolutely surely give spark? Does it run the fuel pump? Are you just missing the 12 volts at the injectors? The ecu controls the injectors by earthing them. I'm sorry to be too lazy to read the thread again so these may be stupid questions...

Engines are pretty simple after all. All you need is fuel, air, spark and about correct timing for each.

Have you checked your engine timing from the flywheel? Front pulley mark can be way off.

Even if your ign output stages would be mixed it should bang randomly in your exhaust. Tried and tested many times

[RS2]

Yes sure it gives a spark, if you check the vid (on previous page) you'll see me earthing out the injectors one by one and then trying to start it. It fires and momentarily runs up to about 600rpm and then dies. It's just running on the fuel I've sprayed into the inlet ports.

I have hard wired the fuel pump (just for now - not a permanent thing) so that it runs constantly. It's just circulating the fuel around the system.

Yes I have 12V at the injectors, they're just not being earthed by the ECU.

Flywheel timing marks are a prob as the engine is bolted up to a Porsche 996 gearbox with no timing holes... I'll pull the plug out of No.1 and check that the crank pulley timing mark is where it should be.

I've bought a new crank timing sensor and swapped that between both G4 and G28 sensors to check that neither of them is stopping it.

Within Vag-com I'm getting an rpm register (which is how I know the highest rpm that it's got to when trying to start so the ECU knows the speed of the engine turning.

Once there is fuel entering the engine, it tries to fire.

I'm still not convinced about not having to wire up inputs from the gear selector as it's from an Auto. I know that several people have said that I shouldn't need to but nobody has the information as to what these ECU pins (42, 51 and 54) should see when the selector is in P or N.

Within Vag-com, Engine ECU, Measuring block 005, Bits bin (4th window) is to do with the gear selector as I've located the 3 wires which would normally be connected to the Engine ECU and atleast one of these changes from a 0 to a 1 when earthed out.

I could do with someone plugging in and reading these off and what happens when in different gears. Also, I'd be interested to see what happens if someone tries to start their Auto via the starter motor (not ign switch) when the car is in D.

I've checked the feed wire which would normally trigger the fuel pump to run (i.e. when the engine turning) and there is no feed from it... I'm guessing that this is on the same lines as the injector earth trigger...

MG

[andy10v]

I thought the autos would not start unless they were in park? (just a thought, it could be v8 swaps or something else I am thinking of)

[RS2]

I thought the autos would not start unless they were in park? (just a thought, it could be v8 swaps or something else I am thinking of)

My thoughts exactly.

Earlier this evening, a friend with his S6 Auto popped by and I plugged VAG-COM in and read off some values.

Within measuring blocks 005, block 4 has 4 digits. The 4th digit tells the engine ECU if the selector is in P or N with a 0. Any other position gives a 1. The 3rd digit is for kick down and is on 0 until the switch is depressed when it gives a 1. On my friends S6, all digits were on 0 when starting.

I used this info and went back to my engine. I found that pin 42 (brown/green) being earthed out gives a 0. It's default without being connected is 1. Pin 51 is the kick down. Earthing this out gives a 1,0 is the default.

I have yet to discover what the 1st and 2nd digits are for.

Despite all of this, I still have the same result... Spark but on fuel injectors being activated by the ECU. Humph!

MG

[UrS4boy]

Hmmm....Good info regarding pins 42 and 51 but you missed an opportunity to try that other ECU in your T3. The reason I say this is there might be an issue with the Holding Relay in your ECU. The Holding relay provides the power to the injectors prior to starting before handing off to the J17 Fuel Pump relay. I know say you have power to the injectors but....

Here is some Holding Relay info (follow the internal hyperlinks, as needed):

http://forums.quattroworld.com/s4s6/msgs/102009.phtml

Here is some fuel injector info (in case it might help)

http://forums.quattroworld.com/s4s6/msgs/20441.phtml

Dave F.

[UrS4boy]

Updated AAN ECU T55 pin-out info

I have yet to discover what the 1st and 2nd digits are for. MG

I have used your new info to update by AAN ECU pin-out post for pins T55/42 and T55/51. In going through that post, there are three or four T55 pins that are automatic trans related, i.e. 42, 43, 51 and 54. "54" is somehow automatic trans-related but I don't know what 43 does. However, my guess is 43 and 54 are the other two digits in measuring block 005. Check to see if they are "0". Maybe something more needs to be grounded/earthed out. I don't have autotrans AAN ECU wiring info so I can't be more helpful.

Updated AAN ECU T55 pin-out info:

http://forums.quattroworld.com/s4s6/msgs/21009.phtml

[RS2]

Thanks,

My friend may be coming across again on Friday so I might try running my ECU on his car and while it's disconnected, check out the other pins with a multimeter.

MG

[RS2]

Small update:

I've borrowed my mates Audi S6 Auto (which from what I understand will soon be fore sale!) and in return for keeping it for a week, I'll try to fix the cruise control and fit a pair of tyres.

I've already swapped over the ECU into his car and guess what... it fired up immediately and ticked over perfectly. I didn't even have to re-code the immob ECU to accept it. I seem to remember that that is possible within the same country regions from messing around with TDi ECUs but as soon as you try one from a different market (i.e. Germany) you have to recode it.

Anyway... I've also checked pin readings from the ECU plug re Auto inputs. Pin 54 gets some interesting voltages. In R, I get 11.2V and in any other gear, I get 10.4V. Not sure why. Pin 42 checks out as before. No continuity in all but P and N.

I get the feeling that there's something simple that I'm missing which will be very obvious when I find it!

MG

[UrS4boy]

Well at least you know your AAN ECU is good. At this point, if you do indeed have good working G4 crank position sensor (and flywheel pin), G28 engine speed sensor and G40 Cam Position Sensor, the issue has to be the Park/Neutral pins that need to be tricked on your autobox AAN ECU.

Or not.

[RS2]

Lol... thanks!

MG

[RS2]

Woohoo!!! it lives!

After using the S6 to check the wiring against, I discovered 2 wires which I had connected incorrectly and it immediately tried to start.

It wouldn't catch though and going back to the injectors, I pulled the rail out and checked to see that all were firing. 3 were and 2 weren't. I remembered that when I was firing the injectors manually, 2 of them weren't sounding like they were opening and sure enough, it's the same two.

Both had a feed so I gave them both a sharp crack and they also started working.

This time it fired up properly and ran!!



Hmmm looks like you tube doesn't work on here.

http://youtu.be/4hqVzcVcRZU

Now the hard work starts with everything else.

Thanks to all for your help and patience.

MG