AAN in T3 Syncro 16 - misfire above 10psi boost

[RS2]

Great info there all, thank you

I've just bought an 044 Bosch Fuel pump. The outlet from the fuel tank is 12.5mm o/d and I think 9-10mm i/d. I presume that that's going to be enough to flow 280bhp?

I'll swap it out as soon as I get it and have a chance.

Yes I've transplanted the complete immo setup over and have to retrain the immo ECU each time to accept the different engine ECU - not an issue. I'm fairly quick at it now!

I've tried to take photos of the chipped ECU but I haven't managed to work out how to pull to the two boards apart yet and I'm not prepared to try and force it. I have managed to see enough to know that it's been socketed and I think that the auto ECU is not socketed.

I didn't realise that the auto ECU could be fitted with manual chips and that that would give me a standard setup. Sounds like a plan.... thanks. I have socketed ECUs before, just not this specific one so I'll order some sockets and get it done to the auto ECU.

The 3 bar map sensor is an external version which is connected by nasty crimped connections on the wires (which have been soldered onto the board). I have been meaning to replace these with OEM connectors but again, haven't got around to it yet.

I'm happy to run bigger injectors if need be. I wish that the original seller was around but my memory seems to tell me that it was a friend of someone the S2 Forums who had it, rather than an S2 forum member. It's that long ago now that I don't have any details to contact them.

I'd consider getting it to MRC for tuning but the van won't fit in the test house It's around 3 meters tall!

I wasn't really planning on changing the turbo or exhaust manifold. 280-300bhp is enough for a 4WD Camper.

MG

[twoqu]

From what I remember the European MTM conversions for the ABY (S2) and the AAN differed as it was the AAN that got the 3 bar map sensor and the ABY did not although the power rating was the same. Anyhooooow......
Its just that the OP says he has a 3 bar map sensor which is unusual for the first stage of modification. I can only remember MTM offering this, as proved by your previous posting from QST! There may have been other vendors.
Still a few questions to be answered before we can make progress. Personally I think its a bit of a risk to run SW that you are not certain is designed to run with the other components you have. Perhaps it might be more apparent when it is inspected. Unless of course the vendors ID appears in the ecu field using VCDS.

[UrS4boy]

Agree with almost every word.

Subtle disagreement: In fact MTM did at one time have a Stage 1 that used the OE AAN 2.5 Bar (250 kPa) MAP sensor. At the same time they also had a MTM Stage 1+ that used a 3.0 Bar (300 kPa) MAP sensor. This was the 280 hp version. Stage 1 was more around 260 hp. Both used stock turbo and injectors. Both involved an encryption board under the fuel/timing chip on the top board. (Bottom board = boost)

Bottomline: RS2 has to figure out what he has or post photos so we can help him more.

[twoqu]

Other than repeating what has already been said, you need to determine what you have got.
If the stock ecu is available I suggest you open it up and see whether its socketed. If it is not, then socket it. That way we can get a manual SW, either ABY or AAN into it. That gives us the ability to see whether the vehicle performs as stock. If it doesen't then the issue is with the installation. If you send me the stock chips I will erase and reprogamme them with a stock manual config. Effectively that will make the ecu a manual variant not an auto variant and rule out any SW conflict.
Actually I was wondering how you are a running a immo ecu (551D). Have you transplanted all the necessary immo stuff as well, the key barrel, immo box etc, or got round it some other way? If not, then that ecu must have other SW as it should not work in an umimmo vehicle.
I would also look at the inside of the modified ecu. IF it was an MTM ecu then it would have a proper 3 Bar Bosch Map sensor and the fuel/ign chip (top board) would have an encyption board on it. There may be others but MTM did as Dave has shown for the AAN only, use the 3 Bar map on the first stage, which most other conversions did not. This would have added to the cost. It did not increase power at the top end so it was to fatten up the mid range torque. Presumably they needed to get over 1.5 Bar to do this.
Most of the conversions exploited the full potential of the standard components to minimise expense so are nearly always in the 270-280 BHP range. Anything above that would need expensive additional components, turbos, injectors, map sensors, manifolds etc, with the SW calibrated to match. So unless you know for certain what SW you have and for what components, you will be chasing the solution. Guess it depends on how much time and money you want to spend doing this.
Pics are always good as sometimes we can spot things.

[UrS4boy]

Somehow, you need to find out what the software in the chipped ECU expected for injectors. Using one conventional nomenclature



or from Mike Hoppen in Florida:

MTM 280HP software with 3 bar sensor $725
Designed to be used with original turbo)

MTM 335HP software with 3 bar sensor $795
Designed to be used with RS2 turbo, RS2 exh. manifold and OE injectors)

MTM 350HP software with 3 bar sensor $850
Designed to be used with RS2 turbo, RS2 exh. manifold and RS2 injectors)

Me: To be honest, from what I have seen anything over the 280 hp option needs bigger injectors

[RS2]

So.... a follow up on the S6 lump and daily running.

Having plugged the stock ECU back in and got 7-8psi boost (found it dismally slow) and no misfires so I've put the chipped ECU back in.

Yes I know... it's risky but I'm working through this.

I think now that the misfiring that I've been suffering is in fact detonation... not good!

I've started a different job in the aviation industry working on refuellers and dispensers. As a result, I have access to some fairly high octane fuel now and again. I'm running it on 100 Octane fuel and it's a lot happier!

Until I get things upgraded, the van won't be going very far and if it does, it'll be on high octane fuel or with a light right foot!

Thinking back to when I bought the ECU, I have a vague recollection that the seller mentioned running bigger injectors. That makes sense as bigger injectors (inc higher fuel pressure) would richen out the mixture somewhat.

More research (on this and other forums) have proved to me that yes, you're all right, it's too much boost for a standard injection system.

Other research on what fuel pump I'm running and it's not up to it either.

It's no surprise that I'm having issues...

Time to upgrade the injectors, FPR and fuel pump.

The question now is which injectors to run and what fits in place of the standard ones?

Time for more research...

MG

[UrS4boy]

G61 and G66 Knock Sensor info

Just out of interest, when the ECU detects detonation, how does it back off the power? MG

I am sure PRJ has posted the answer on the forum before - IIRC it cuts boost and pulls timing

More G61 and G66 Knock Sensor info:

http://forums.quattroworld.com/s4s6/msgs/21047.phtml

[twoqu]

http://www.s2forum.com/forum/showpost.php?p=552504&postcount=5

What fuel do you put in it?

[Error404]

I am sure PRJ has posted the answer on the forum before - IIRC it cuts boost and pulls timing

[RS2]

Just out of interest, when the ECU detects detonation, how does it back off the power?

MG

[twoqu]

My memory is terrible for this kind of thing. Is the 3 bar MAP sensor going to cause issues with stock chips?

MG

Yep!
Thats the problem at the moment. Frankly we cannot even verify that the chips in that ecu are compatible with that map sensor!

[RS2]

I though the modified ecu had that external 3 bar map sensor from the pics on your original thread about the conversion. If so the internal map sensor has gone.

My memory is terrible for this kind of thing. Is the 3 bar MAP sensor going to cause issues with stock chips?

MG

[twoqu]

Hmmm, I guess that at 12psi that would be about right for the lower end. I'm using a VDO boost guage to read the boost level. I rate VDO but nothing is perfect. I am right in thinking that you can't read boost in measuring blocks aren't I? I couldn't find it.

I'll stick up a wanted add for a set of original S6 manual chips and put them in the modified ECU. Hopefully, the internal MAP sensor is ok as it's still there...

MG

I though the modified ecu had that external 3 bar map sensor from the pics on your original thread about the conversion. If so the internal map sensor has gone.

[RS2]

Oh, it's slow with stock boost

MG

[RS2]

Bit frustrating as I appreciate you need to keep using it.
Certaintly if you can scare up some stock chips and you can socket the ecu that at least gives you options. The chips that come out can then be used for the other ecu if you choose to get a decent known set up. Most reputable reprogrammers tend to use the OE chips as they are superior to domestic computer ones.
If we can get the correct manual SW in that stock ecu then personally I think thats a good thing.
I have just looked up the stock AAN boost levels which are dependent on altitude and outside temperature. Assuming you are not above 1600M then at 0C boost should be between 1.84-2.00bar absolute and at 20C 1.99bar -2.10 absolute. So as we are nearer the former its not that far out really.

Hmmm, I guess that at 12psi that would be about right for the lower end. I'm using a VDO boost guage to read the boost level. I rate VDO but nothing is perfect. I am right in thinking that you can't read boost in measuring blocks aren't I? I couldn't find it.

I'll stick up a wanted add for a set of original S6 manual chips and put them in the modified ECU. Hopefully, the internal MAP sensor is ok as it's still there...

MG