VonOettinger '91 Multivan Syncro 3.2 WBX6

[VonZu]

Hunting - two types:-

1) Rhythmic (Brmmm, Brmm, Brmm ), rich -tends to get the better of you in low gears jerking the vehicle about when off the gas... neutral throttle

2) Erratic, longer period, splashy, weak - tends to no real power or torque and tendency to cutting out, whereas above tendency towards pulling well and staying running.

I'm absolutely in the rythmic section with mine. And as said earlier, it can be dead stable while warm.[/quote]

I just read this thing again.
I have rythmic idling, jerking when off the gas (kangarooing), emissions off the scale, no tendencies towards loss of power. I feel pretty confident that it's getting too much soup.
All the SA Oettingers have the idling and jerking syndrome.
The main difference between the wbx6 and the wbx4 is the distributor and the injector wiring (?).

I wouldn't be surprised if things changed a bit if I put in new injectors.

[32wbx6]

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.

Just a thought, I shouldn't tell you all this as you have just bought yours I sincerely hope you find yours is curable or ok to live with

[VonZu]

That's a good list, if I ever saw one.

And I can't help but mentally nod to myself when I see what you haven't done. I would just love if my inexperienced hunch would end up being the fix in this.

I've asked vwspeedshop if they have injectors suitable for the 2.1, and also about the impedance across 6 injectors. I've also contacted a local T25 colleague who's got several 2.1 laying around. Maybe I could find some good injectors there. I'm not to keen on investing in brand new injectors witout beeing sure about it.
I'm tempted to take 6 injectors from my two other 2.1, as I am pretty confident that they are working quite well.

[Aidan]

most engineers that offer an injector cleaning service also test them and check the spray pattern and the flow rate before and after cleaning, in the UK 4 for £75 inc p and p return 24 hour service is possible so for £100 you should be able to get your 2.1 ones checked out before trying them, better than spending £600 on new ones
afaik the DJ and MV in our market have the same injectors, the colour variations we see, green, yellow and blue plastic bodies are just production variations the injectors have the same flow rate and the injection system is the same on both variants

[HarryMann]

I am going to wire my fuel pump dirctly to battery so that its is not "switched off" by ECU to stop injection flow at 15oo revs and then see what happens as an experiment. Assumption here being that the instruction or mechanism of fuel shut off is the fuel pump switching off and then on again? I believe its also a safety mechanism to stop fuel flow in case of accident? Please stop me now if someone knows that that definately isn't the case

Pump probably (almost certianly) not switched, but don't let me stop any experiments to find out for sure

A raid on their facilities sounds in order

Definitely, start tooling up and making plans Bond

Since the type of unstable kangarooing can occur on a carburrettored engine, and for other reasons, could I suggest that you think along the lines not of the fuel supply 'switching' or injection 'switching' erroneously, as much as just being fuelled, overall, plain wrong...

It is just a feeling that I have, that engines of a certain type, and vehicles of a certian mass and inertia, with a certian transmission complaince (whippiness ) at certain throttle opening that happens to be near closed but not quite, at a certain rpm, usually lowish, but not always...

...can tend to become speed unstable, sometimes alarmingly so. This is not always solely the engine, but the combined dynamic system.

In fact, I can make my diesel powered Syncro kangaroo badly if I don't modulate the throttle quite correctly under some situations or slip the clutch just a bit sometimes e.g. speed instability on neutral throttle, or very low throttle when slowing down, could in fact be a 'feauture' of the T3's mass, and transmission/engine mounting wind up compliance. It's always there, but just accentuated with the Oettinger... maybe

Unfortunately though, I am not sure if this suggestion above will actually help you much...

[32wbx6]

It is just a feeling that I have, that engines of a certain type, and vehicles of a certian mass and inertia, with a certian transmission complaince (whippiness ) at certain throttle opening that happens to be near closed but not quite, at a certain rpm, usually lowish, but not always...

Thanks Harry for your feedback. I must say that some of us here are wondering about things as per your comment above. I often wonder whether the flywheel as an example is not big enough for the 6's output. I think of the old Fôrd V6 conversions that were done here years ago into buses of all types. In those cases the flywheel of the V6 was transplanted too as it was felt that the motor needed it to aid in all the "balance" attributes. Also I feel by now that I would have found something that seemed to point to the error and the fact that so many 6 owners complain of the same thing, perhaps it just has to be lived with. I am almost glad to hear your diesel can also get itself into a knot now and again, I feel much better

I am now going to check injectors again, measure the fuel pressure and do one last experiment with the "overidden fuel pump" and then I am calling it a day and will live with it. I then will post some pics of some awesome places in SA that we get to play in just to change the subject. A genuine thanks to everyones feedback, comments and suggestions

[silverbullet]

Might I just add to Clive's comments about drivetrain flex/whip or otherwise spong-like tendancies: A clutch friction plate with "tired" damping springs can also give these symptoms when pulling away or driving at low speed in low gears. Nothing to do with a hunting idle though...

[PetenAli]

Might I just add to Clive's comments about drivetrain flex/whip or otherwise spong-like tendancies: A clutch friction plate with "tired" damping springs can also give these symptoms when pulling away or driving at low speed in low gears. Nothing to do with a hunting idle though...

Silverbullet - your's and Clives comments are really fascinating as I have these symptoms with my 2.1 DJ - usually trying to pull away in second gear at low revs and usually only when the engine is warmed up. All I have to do is dip the clutch and all is fine. My idle is also absolutely spot on whether the engine is cold or fully warmed up. (I check it regularly when I do the timing.)

Sorry if this is a bit of a hijack but there are so many similarities between the fours and sixes that it seems like it might be relevant.

Pete

[VonZu]

These just arrived:



Which means that it's going back to the proper Oettinger front

[HarryMann]

Blimey, spending money, that's a good sign of a love affair burgeoning

I am almost glad to hear your diesel can also get itself into a knot now and again

Yes, they often do, and I haven't forgotten that its a 1.9 with JX flywheel, so a bit light maybe too

It would be interesting to know then, if all the engine mountings, the flywheel and the clutch plate are Dj spec. ?

====

Last thought on this for a while... whatever helps, would imagine it'd be less rather than more fuel, in crude quantitive terms.

anyone tried backing off the ingition timing a fair bit, just for a quick test of a retarded setting.

[ Ever seen movies of vintage race cars pulling away (very high gear, very low flyhweel mass, very 'iffy' carburation, lappy cams, probably verging on the overly rich side for safety)... they would often snatch and jerk like wild dogs until settling down and pulling like a train ]

[32wbx6]

anyone tried backing off the ingition timing a fair bit, just for a quick test of a retarded setting

Have tried that, played with timeing and mixture etc enormously, doesnt seem to help much. Vehicle either starts stalling on take off or runs very strongly but still surges and kangaroos.

Sorry to report that on Wednesday I used Syncro to work and while cruising perfectly suddenly she missed like mad and motor running on all about 3 cylinders, one bank only . I stopped and got her towed in, looks like left bank has either broken rocker arms or valve springs gone. I will see her later, she in ICU currently and left head is coming off to look see

Very frustrating, thats two major problems with this motor and shes only run 30 000kms since supposedly perfect rebuild First the cam gear broke, apparenlty one one their weaknesses and now this....I really need a reliable motor as I actually want to use her to do Southern Africa like I used to with the original 2.1. That motor was awesome actually. Since the conversion I havent traveled again, just dont trust this motor, sad to say.
So I need to think, perhaps i must go to Golf 2.0. Most popular conversion in South Africa or ideally Subaru 2.5.... I see lots done nicely in UK We dont really do them much over here so a bit wary to tackle it. Be horrible to go to Golf after wbx6 in terms of pulling power... at least i can stop worrying about my gearbox then

[silverbullet]

Bad luck. I have it on good authority that wbx6's are known for breaking middle cylinder rockers and eating the corresponding lobes of the cam as well, no direct experience of them as yet.
You could always find yourself an SVX motor to stay flat-6, similar capacity to the Oetti but rather more "get up and go"

[syklist]

Hmm... I tried to post som pics from Picasa web albums, but only get an error message about "being unable to determine size". I've never had problems with posting images like this before. Are there any issues related to Picasa Web albums?

The pictures are on the norwegian thread, on page 2. But I would like to post here directly.

I got that error when I misspelt the file name and hence the URL was wrong. Click on the Img button at the top of a post, copy paste the correct location between the [ img ] and the [ / img ]. I put my pictures on my own webspace, so I had to allow images to be displayed here on the club80-90.co.uk domain (disabled HotLink protection for this domain). I don't know if this applied to Picasa.

[VonZu]

After a bit of fiddling, I found a simple workaround for the picasa issue:
https://club8090.co.uk/forum/viewtopic.php?f=1&t=95890
It was the s in https.

[32wbx6]

You could always find yourself an SVX motor to stay flat-6, similar capacity to the Oetti but rather more "get up and go"

.

Sounds good, one being built here currently, but it actually has a lot more beef that the wbx6, wbx6 actually very old tech now, so the 2.5 Suby is closer in power etc. In fact they are almost idfentical in torque and power output. I think the SVX is going to break the gearbox very quickly I think I will look at the 2.5 if anything from Subaru.