Syncro 4&4 Discussion and Q&A last answered over 2 years ago.
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Hi all, I'm new to the site and from South Africa where our Syncro forums and clubs are growing rapidly at last. Suddenly everyone seems to want one
My question please if anyone can help....Does anyone out here have an Oettinger WBX6 3.2 motor in their bus that runs properly with regard to idle "hunting" and "surging" or "kangarooing" at low revs? If so please let me know as we are desperate to solve these issues if possible on these motors. In South Africa none of these motors run properly and we have been trying to solve the issues for a long time. There is an imported one from Germany in this country and it runs perfectly, Oettinger installed the motor over there themselves, so it can be done, somehow we are missing something in South Africa with respect to these motors. Oettinger and VW SA have no idea and cannot help at all.
Hi john, I assume if vw have been involved then all the obvious things have been checked? But I would still start at the basics - all earthing points must be clean, check ecu plug and loom for broken pins/wires, check air and coolant temp senders, check throttle position sensor/idle switch, fuel pressure regulator. All these things will affect idle speed, and there could be more than one fault and still run ok(ish), so work through and test them all first. Does it have the same idle air bypass valve as the 2.1dj? Is it worse hot or cold?
The Campershack - (website paused) WBX Rebuilds & Upgrades from the beautiful Isle of Arran
Hi, thanks for the response! Yes all obvious things checked and through time have run motor with replacement ECU's, AFM's, etc. Loom completely checked for continuity etc. What is worrying is that all the WBX6's here do it, except the imported one, which makes one wonder perhaps about our fuel or something like that. I have also compared all parts and serial numbers against the German ones layout and can’t find anything obviously different.
It has the exact same management system as the 2.1 except for a differently mapped AFM and the ECU that was also done for Oettinger and this engine. I have an original manual from internet (amongst others) that was produced by VW years ago on how to follow a sequence check on the entire 2.1 system. I have followed this and cannot find any faults or readings that are out. One of the guys who installs the motors is ex Oettinger himself and says he never could get them right here either!
One area of concern for me is the ECU was made for Oettinger in Germany. I wonder whether the pins on the multi pin plug into the ECU may be different in this country and so doesn’t correlate correctly say with the German ECU. I question this as there were apparently subtle differences here with the DJ 2.1i which were done for local conditions. Very hot, lower fuel qualities etc. Unfortunately we don't have anyone here with the kind of expertise to look into the ECU itself. Also so few left I am loath to go tinkering.
The other interesting point is that if you disconnect the fuel overrun shut off switch (one switch of the pair being overrun shut off and high load fuel enrichment) the motor then still hunts a bit at idle but the surging or "bucking/kangarooing" disappears completely. Happy to run it this way except you then lose cold start ability which unfortunately is also mapped through the overrun shut off switch at ECU level. It does point somehow to the fault being in the engine shutting fuel down on de-throttle and then apparently refuelling too much, causing the bucking? The switches have obviously been checked very carefully and I have run numerous new ones and old ones to get a comparison but all do the same.
From what I've seen of the pre 1992 (and a good deal of the later run too) SA vans they are basically german supplied parts apart from the body and interior made locally and that includes the wiring looms, they have bosch germany labels on them so I'd be surprised if the pinouts differed, though the oettinger is more MV (Digifant) than DJ so may have the MV pinout which is different to the DJ one but easy enough to check that gainst the Bentley manual - the Dijijet system in that although 1.9 is the same pinout as the euro spec 2.1 DJ
DJ only has one idle switch that switches twice, once at each end of action.
Good point Aidan, I have missed that all along, that the 2.1 DJ has only one cut offswitch, switching twice in operation and the 6 has the two switches. That may make it possible that the ECU being more MV and the loom being SA made are not compatible....I will spend some time down this particular rabbit hole, thanks for that!
My 3,2 is having the same problem. And it was installed by Oettinger in Germany.
When the engine is cold, idling is always unstable. And Norway is relatively cold at the moment.
When it's warm, it's not unusual for it to idle just fine. But, I am then able to produce instability by switching on things like the heater fan etc. The radiator fan has the same effect.
That being said, there are a number of electrical issues on my car. Electrical windows, sun roof, eber control etc. all won't work. It will be interesting to see if there is any noticeable change after fixing those.
Unfortunately, I won't be doing much to this car for a little while. Other projects currently have priority.
But I will follow this thread with interest.
Current: '91 Oettinger Syncro Mutlivan 3.2 - '90 Autohomes Komet 2.1 - '87 Syncro Half-panel 2.1 - '85 Transporter 1.9 - '77 Bay 1600 Ex:
'90 Autohomes Komet 1.6TD
I see everyone keeps up this conversation on your other thread! So I have also posted a response there...sorry!
I am interested to see you say you only have the erractic idle and NOT the kangarooing effect. I am actually glad to hear this(I think ) as I have never been sure if the two symptoms are linked or separate issues. Still not really sure.
I will hopefully iron out the different wiring question on Thursday as I have his imported van for the day.
Weird thing. The whole discussion ended up there. But, no loss. Just a longer project thread.
And now I won't say anything about the idling here. Over to the discussion
Current: '91 Oettinger Syncro Mutlivan 3.2 - '90 Autohomes Komet 2.1 - '87 Syncro Half-panel 2.1 - '85 Transporter 1.9 - '77 Bay 1600 Ex:
'90 Autohomes Komet 1.6TD
VonZu wrote:
When it's warm, it's not unusual for it to idle just fine. But, I am then able to produce instability by switching on things like the heater fan etc. The radiator fan has the same effect.
When the electrical load on the alternator increases, there is more current on the grounding conductors for the trans, engine, and battery. The engine sensors for the most part share these same ground paths, and of course every circuit in the vehicle uses the battery ground conductor. So when there is resistance in any of these ground conductors and/or their connections, the increased current from a large load causes a voltage drop along that path. The sensor value is now relative to the now elevated voltage at the end of that conductor nearer the sensor, instead of to a true zero voltage, which alters the sensor value the ECU uses, and you get all kinds of erratic behavior. It's called a "ground voltage offset".
So all these ground conductors and their connections have to be improved, and with the age of the copper and crimps in most of these vehicles the best thing to do is to install new conductors. Lots of people tend to the engine and trans ones but neglect the battery ground, which is the most important one of all. I also add a dedicated ground conductor from the alternator chassis either to the trans casing or to the bodywork, to take the heavy currents away from the engine ground strap.
Wel it can only make things better, even if it doesn't clear all the problems you'll know that things have a better foundation to work from. Don't forget the battery ground, though. VW bolted that strap right to painted bodywork under the seat, relying on the bolt threads for contact. The same bolt goes thru into the wheel well, and once the little nubbin of undercoating cracks the bolt threads just wick up water and corrode away. That connection carries every electrical load in the car, turn on the hi-beams and there can be a 2V drop on that connection alone! Clean the paint around the bolt hole to bright metal, install fresh copper with a stainless star washer in between to bite into the metal, and wow! the headlights will be brighter, wipers and fans will run faster, all kinds of things just work better if that connection is good again, and most of them are in pretty bad shape unless someone has tended to it.
Bitchin' Oettinger, by the way, I wish there were some of those engines laying around here, I'd love to have one in my own rig, and being the wbx guy it would be a feather in my cap. You guys get all the cool cars over there, VW acts like they hate America, guess we don't buy enough friggin' cars or something.
tencentlife wrote:. Don't forget the battery ground, though. VW bolted that strap right to painted bodywork under the seat, relying on the bolt threads for contact. The same bolt goes thru into the wheel well, and once the little nubbin of undercoating cracks the bolt threads just wick up water and corrode away. That connection carries every electrical load in the car, turn on the hi-beams and there can be a 2V drop on that connection alone! Clean the paint around the bolt hole to bright metal, install fresh copper with a stainless star washer in between to bite into the metal, and wow! the headlights will be brighter, wipers and fans will run faster, all kinds of things just work better if that connection is good again, and most of them are in pretty bad shape unless someone has tended to it.
I agree on the earth comments. Two threads a bit muddled now, so copying over list of checks done on wbx6 motor from other thread re idling issues. If this thread grows again so be it!
I also have extra heavy duty earth straps from trans to body and from battery earth to body, found it also helped the wbx6 start when hot, starter battled otherwise.
Out of interest I have now done the following checks:
In most cases we cannot get new parts so I borrowed used parts where possible;
I have swopped out, borrowed, begged or stolen the following....
1 The ECU - no difference
2 The idle stabilizer valve (8 different ones to see if the A, F, C etc part number at the end made a difference)- no difference.
3 The idle stabilizer control unit (behind tail light), at least 5 diferent ones. All different reactions but none that worked properly.
4 The Air Flow Meter - 2 others - no difference.
5 The stabilzer control unit in the plastic box, near coil. - no difference.
6 Throttle overun cut off switch, tried at least 5 and bought new one from VW when they still had some left. - no difference
7 Swopped out TCI unit - no difference
7 New coil
8 New spark plug leads.
9 Have scoured the Haynes and Bentley manuals and re read and absorbed and run tests as described many times. I cannot find any diffrerence in readings.
10 Have had the motor "tuned" by myself, the original installer and a friend who is pretty clued up and we have never managed to cure it.
11 Have recently compared the wiring etc against the only imported Oettinger I know that runs beautifully. Cannot find anything except it has an Oxygen sensor which i dont have.
12 Have re-set the tappets more times than I care to remember.
13 The same goes for idle, mixture, timing etc "tweaking".
14 Have tried various restrictors of differing sizes in the crank case venting sytem. Have read up on crankcase venting and then tried experimentimng with the layout - no difference.
15 I have dismantled and rebuilt the plenum, AFM hosing, crankcase venting lines etc many times to check for any air leaks.
16 I have soldered ALL joints and earths and have checked for continuity etc.
17 I have had the injectors serviced and pronounced ok.
She runs like a dream, just wont idle all that happily and does the kangaroo dance at 1500 revs! I love her but she is also driving me crazy
What i havent done:
Measured fuel pressure
Bought new injectors, and maybe you are right about that Perhaps I need to...
Swopped out the dizzy, although I have checked wiring, functionality, vacuums and hall sender unit tests come out ok.
) as I have never been sure if the two symptoms are linked or separate issues. Still not really sure.