Golf MK1 1983 with 1989 GU engine, automatic and "pierburg 2e2"

Hi there, pardon my partially bad grammar and typos.
My name is Erik, and a norwegian golf mk1 enthusiast, new here ever since i tried firing up my old car after a year of "garage travel"
i am having a bit of a quarrel with my carb.

My problem is that i dont think i get enough vac on my vac hoses, after changing all of them, taking the carb apart and cleaned and blowed through every bore i could find.
Iv changed my choke pulldown, checked my stage 2 throttle unit, seems working fine, but does not seem to take action upon full throttle.
Is there any guru in here, that would concur with my reasoning for that it would be the idle boost control and the TTV valve that is malfunctioning, since there is no different behavior when disconnecting the wiring (originally disconnected and vac hoses not connected according to either pierburg manual, or Hayes vw mk2 jetta/golf manual.) I did reset most settings according to manual, but now fails to go any higher RPMs than 2500-3000, and got a tendency to die out on my by means of "kick-down" to try hit higher rpms.

It also occurred for me that i may need a second idle boost valve, to help regulate idle for my gearbox when selecting gears.

I may need to adjust my acceleration jet amount a bit, since it seems to drown?
And it seems a bit "rich" because of some times wet sparks or at least very sooty.

I would rather not change my carb, i would prefer to get it working.

That would be my questions at this time.
And at this point all i want is to get it running more properly, rather than getting the CO correct

 

Hi, welcome to the forum.

 

I have to add that i've taken out the distributor and turned it, along with my cam, changed my hydraulic valve lifter buckets, timed and re-timed my engine numerous times, all in effort to get it to hit high response and proper reaction when hitting the pedal. But as it seemes it is worse now, than what it was for a year ago, when it was hard to start, hardly at all without start gas, but with either the dizzy 180 off, or cam 180 off. or both cam and dizzy, not sure right now.

 

Hi Erik.

I'm not sure what is going on with your engine and carb, but I have a few questions which may help to clarify some things.

You say you have checked the stage 2 throttle unit; how did you do this? How do you know that it is not working at full throttle?

As you may be able to see if you look carefully, following the shape of the lower casting from the vacuum port where the stage 2 diaphragm connects, the vacuum which powers the stage 2 diaphragm/vacuum motor comes only from two drillings, one in each barrel of the carb, at about the height where the diameter is at a minimum (the venturis). This means that airflow past these holes is the only thing which can cause the pressure drop necessary to move this diaphragm and open the secondary throttle.
None of the other vacuum pipes are connected into this system, and this system is not connected into any other source of vacuum (e.g. inlet manifold).

So I don't see that the TTV or any other items with vacuum hoses can be affecting this.

When you removed the carb to strip and clean it, was the rubber mounting flange in good condition?

Will the engine rev to higher than 2500-3000 with the gearbox in Neutral?


Do you have any photos of the carb?

 

The foot has been changed, although no effect.
How i know, well i've sucked on it with both a vac meter, and orally, bur truly does perform better with me suck on a tube, rather than that vac meter i got. not tried in neutral yet, but should it be any different from park to neutral?
Well, it does not or did not respond quickly enough when trying to achieve any normal response now that the vac hoses has been set up in many ways acc to the manual, still no working second stage.

If i may have switched the two "jet screws" by the floating device would this cause it to get so much excessive fuel ?

 

OK so I guess that unless the little drillings I mentioned are blocked up with dirt, the stage 2 throttle unit is working correctly. You can probably clear any blockage by shooting carb cleaner down a vac hose that is connected to the port on the carb where the stage 2 unit is normally connected. You should see two tiny jets of liquid squirting across inside the barrels of the carb if you try this. Don't shoot carb cleaner into the stage 2 vacuum unit by mistake though, I don't think the rubber diaphragm would like that.

It sounds like you are expecting to see it working by just revving the engine while the engine is under no load?
I don't think this will ever happen. The engine needs to be under high load, with the accelerator pedal about 3/4 pressed or more, for the secondary throttle to start too open; so you can't observe this happening on your driveway, unless you have a rolling road.

I don't know enough about automatic gearboxes to know if the engine should behave differently in P and N, I just wondered if it would rev freely when there is no load on the engine.

According to my Haynes Pierburg carb manual (No. 1785), if you have the correct carb on your automatic transmission GU engine, it should have VW part number 027 129 015Q, and the primary main jet is size 105 (1.05mm diameter), secondary main jet 120 (1.2mm) so swapping them around would make quite a difference.


If you haven't accidentally swapped these jets, I suspect that your trouble is really somewhere else in the engine bay, ignition components are always a good target.

 

Tried to start i neutral apposed to park, but as i already knew that would not affect any reactions to the stage 2 diaphragm
It does by the way seem to be a bit hard to push in if it try to oversteer it manually while actuating the throttle lever.
What puzzles me is that it did in fact rev up last year, as it should have done, but i will probably need to check those two jets down there, just to see if i may have swapped them around, since my carb also has had a tendency to "blow back" some fuel, but this got better after turning my dizzy just bait, and now it starts way easier than what it did when "all" was way off marks..hehe. All ignition parts are new, exept the dizzy.

I do some double checking on those jets and see if that is my trouble, rather than my stage2 unit, which in my opinion should be in function on full throttle, but it may be as you say that it will infact get in action during heavier loads, sounds local since then there would be created more vac.

 

https://www.dropbox.com/s/3mbpojzfv99547a/2013-07-12%2016.55.55.jpg

 

By some reason the pulley on my camshaft is but on in such a way, that when i put it on marks according to "the book" it wasn't right at all. Took off my valve cover and checked when it "changed" on nr1, and the pulley showed somewhere between 10-20 degrees over to be aligned with the edge of the head. No wonder it was hard to get right. Now my 3/4 unit is the one that puzzles my, it works, withdraws and all, but adjusting it is not that easy.
Since i believe i miss having one idle boost relay for the pink line, and connecting that one to the brown may not be sufficient.

Anyone with any experience with these carbs on the automatic trans?

 

How many air/vac hoses connect to your 3/4 point unit, two like in this image?:



Or is there a third one?

If there are just two (you mention only pink and brown) then you have a 3-point unit, not a 4-point unit. As far as I know, only 4-point units require the additional air valve shown as item 112 in the image below, with dotted lines showing where the vacuum hoses go if the 4-point version is fitted.

Not all cars with automatic gearboxes have the 4-point version.



Are your vacuum hoses connected like the first picture, or differently?

Surely if your camshaft was 10-20 degrees misaligned, then correcting this will get rid of all your problems?

Edit: here's a picture of a carb with a 4-point unit, showing the attachment points for the three vacuum hoses, colour-coded yellow, brown and pink. Note that it also has two idle speed adjusters rather than the single one that the 3-point version has.



Does yours have these 3 vacuum connections and 2 adjusters?

 

fixing the camshaft thing cleared out my rev.troubles, yes.

Yes, my hoses are like it is on the pic in the bottom there, yes according to one connection diagram in the pierburg manual i downloaded, i miss one idle boost control valve thats supposed to connect to the pink line (used for aircon/autos) and going in some kinde of loop there (pos nr 112). So instead i hooked the pink together with the brown. And the yellow goes straight on to the idle boost.

 

OK, good news about the rev troubles.


I believe that the valve you are missing (112) is exactly the same type as the one you already have screwed to the back of the carb (97). The switch shown as 113, I think will be turned on when the gear lever is moved from P to D. There may be such a switch already in place near the gearstick mechanism? The control unit (96) will be in or near the fusebox in the cabin if you have it fitted. You may not have it, and the system can work fine without it, the idle control valves have permanent 0V connections in this case, instead of connections that are broken above 1200 revs by the control unit.

I guess at the moment, with your pink and brown hoses linked, the lower adjuster on the 4-point unit has no effect?

If you link yellow to pink instead (which is what will happen if the full system is there when the gear lever is moved to D, switch 113 closes and second idle valve opens) the lower adjuster should start to work. But the idle revs will stay at the higher value all the time instead of changing when you move in and out of Drive.

If you want to implement the full system with the second air valve, and you have any trouble finding one, send me a private message. I have several spares that I don't need.

 

I've got his thing that i wonder about, my car may or may not have been subject to repairs in the chassi, not sure if i remember correctly now. Bought it in 97 or 98, parked it in 99 to keep it until it had come of age, and could be called a veteran.
I modded my car with replacing the original 1,6 with manual, to this 1,8 with auto. Required just enough modification of engine mounting brackets. Quite easy rebuild.

But ever since i bought the car, my wheel on my passenger side (right hand side) is sticking out 1 inch or there about outside of the wheel base, which is kind of bothering me.
So there in lies the question, is there any differences in the lengths of the which bones between the different models and makes of these cars? I know that there is difference in drive shaft lengths, so it would only be natural to assume that the length of the wish bone is different too. But i have not found any information about it.