80 coupe B2Redundant vacuum port Pierburg 2E

tram-man · 18-01-15, 10:52 PM

Evening,

My B2 coupe with 90hp engine has been given some much needed TLC lately.

I have had the car 18 months and it has always idled high 2000rpm and stunk of unburnt fuel inlets really warm. The engine pulls well and I am of the opinion that once all the idle systems are off then basically the carb must be good. The big brass air idle screw has never effected the idle speed and the car struggles to meet CO regs here.

So I have recently pulled everything to take a good look. This is what I have done:

Inlet manifold off, new gasket and rubber oring
Set ignition with strobe as per Haynes
New plugs, leads. Checked wiring to and from TCI dizzy parts
Checked all voltages to carb solenoid, choke, manifold preheater, thermo time switch. Some wires were broken seems now to be OK.
Checked 4 pin coolant thermo switch in water. working.
Replaced all vacuum hoses around carb and beyond.
I have reset the secondary throttle stop as per haynes.
I have set the fast idle screw on the 3 point vacuum things as per haynes
I have pull the top off the carb and blown through the jets etc.

I have found that the pull down choke is defective and have ordered a new one.
The small pierburg heater element has failed. Trying to locate a new one.
The thermo time switch works
The pull up vacuum unit for the secondary venturi works.
I don't know how to check the waxstat

When putting the carb back I noticed that I have a vacuum port unused. I have doubled checked with Haynes and on interweb 2E forums. I have the audi VW SSP67 manual. The vacuum port is on the cylinder head side. According to some diagrams it feeds a vacuum unit for an auto box. I wonder if this has ever been connected and if the carb has been sucking in extra air here. There are 2 ports on the engine side of the carb. A vacuum pipe connects one port to the pull down choke.

Should the other port be blocked? Would this have fed and econometer (which I don't have). The car is a manual and originally from Germany 1984 GL model. It is clear that the car has been tinkered with and I am trying to undo poor workmanship from previous owners...

Please don't tell me to ditch the Pierburg. It looks a great bit of kit and I want to get it working. I have a pair of solex c40's which will eventually bit fit up with another head and cam.

Picture will follow tomorrow,

Thanks, Stuart

Minty · 19-01-15, 07:05 PM

Stuart
A Coupe GL will be near-unique in the UK - get some pics up pls!

tram-man · 19-01-15, 10:16 PM

The GL coupe is also pretty unique here (in Holland) as it was never offered for the Dutch market. Mine was originally a German car. But essentially it is the same as an 80CD sedan. It has a DS high compression block with a Pierburg 2E. The golfs also had a similar set-up and I believe also some Audi 100's.

This is a picture of the set up.

This is the carb slightly rasied off the inlet. Unfortunately I failed to capture both vacuum ports clearly . But one can be traced from my thumb. along the accelerator pump and goes to the port on the front of the carb. The unused port is hiding behind the pipe running to the waxstat and is parallel to the front port (ie pointing toward left wheel).
Both ports seems to run off the primary venturi.

Here is the vacuum diagram for a Pierburg 2e2 (slightly different carb) from the VAG SSP docs. You can see vac line marked C that goes to an actuator for the auto box. But this is for a transverse golf engine

Tonight I plugged the rear unused port. The car starts but runs richer than ever to the point that the unburnt fuel is dripping out of the exhaust.

I need to wait for the new pull down but I am considering opening up the throttle screw on the secondary venturi to allow the engine to get more air as I had closed it up as specced in the Haynes book.

vorsprung durch technik · 19-01-15, 11:11 PM

As far as i can see you haven't mentioned what engine you have.But going by the ref to the 80 CD sedan that will be a 1.9 5cly with engine code Wn from memory,i used to have an 80 CD saloon.Is that what you have? If thats the case these the carburettors fitted to these engines are great untill they go wrong and they always do.The seem to drift out of tune.Thats my experience of them having to take apart for a rebuild and every year or so take top half off and reset the floats with correct measurement. It sounds to me that your is on choke constantly. Damm i had the manual handy a few weeks ago and now cannot find it.

I am wondering if you even have the correct carb fitted as it designation doesn't ring a bell to what i had on mine. But of course for different markets quite often different carbs/emissions used.

Whats you engine??

missfire · 20-01-15, 12:39 AM

Hi, don't know if it's any good but I used this site a bit when I had a B3 carb. Lots of diagrams with keys.

Some pierburgs near the bottom of the page -

http://www.gowerlee.dircon.co.uk/spares.html#pierburg

andya · 20-01-15, 07:03 AM

My old 1986 base coupe b2 was a 4 cylinder 1.8 ds engine. It also had the pierburg carb, but im afraid I lost my patience with it and replaced it with a reliable and easy to work on weber -though I realise you didnt want to hear that!

http://vwa1.dadoghouse.com/?p=16

Found this - a pierburg manual to download. Good luck

tram-man · 20-01-15, 07:25 AM

Sorry, forgot to say explicitly that it is a 4 pot 1800.

Thanks for the tips and links. Yes I believe my choke is wound
closed too far. I have been trawling the web and they refer to an opening of 3mm for the choke. I closed it right down....

Andy, do you still have your Pierburg? If so, could you turn it over and see if the rear port (engine side) has a blanking tube?

Stuart

andya · 20-01-15, 11:55 AM

Hi

No sadly when I wrote my car off, I sold the weber off separately and the old pierburg I donated to someone on here for free! Can't remember who mind you?

andya · 20-01-15, 04:56 PM

Just looked it up, my old pierburg went to BigT80 on here. He took it as spares. Might be worth contacting him via the pm system and see what his thoughts are.

Regards

tram-man · 25-01-15, 04:40 PM

Well I have Fitted the carb with a new pull-down choke and Replaced the vacuum on the dizzy which was not holding vacuum well. Checked the wax stat which works and checked the resistance of all the ignition parts. Rechecked dynamic timing. So all the component parts work now and the car absolutely flys.

I have just plugged the open port as I am now almost 100% convinced that this should have a plug (or is a take off for the econometer or automatic gearbox). I think the plug has always been missing or that the car has back fired and launched it somewhere.

I have bought a vacuum tester (ebay 15quid) in order to set up the rest of the 2E. It still seems very rich ticking over (when warmed up) and I think the whole carb has been played with and I need to reset it.

I have found a link thru this forum to a more detailed set-up of a pierburg 2e(2) which I found helpful. The Haynes coupe manual is very sketchy and doesn't cover the workings properly in the supplement at the back. It is not a link for the Audi carb but it gives a bit more basic info.

http://www.clubgti.com/showthread.ph...urg-2e-problem

What I am really after is an official Pierburg audi 80 90hp set-up manual. Or a VAG workshop manual covering the 2E for the audi application.

On a steep learning but happy to help anybody with similar B2 woes

19-01-15, 07:05 PM	#2
Minty Senior Member Classic Audi Club Member Join Date: Jul 2008 Location: Wirral Posts: 1,528	Stuart A Coupe GL will be near-unique in the UK - get some pics up pls! __________________ 1984 GT5E Topaz Green 1982 GT5S Helios Blue - now in Ireland 1983 GT5E Topaz Green - donor 1986 GT 2.0 Tornado Red - long gone 2001 A6 2.4 V6 - exported to Ireland

19-01-15, 10:16 PM	#3
tram-man Grown up member Classic Audi Club Member Join Date: Aug 2013 Location: Location: Location Posts: 37	The GL coupe is also pretty unique here (in Holland) as it was never offered for the Dutch market. Mine was originally a German car. But essentially it is the same as an 80CD sedan. It has a DS high compression block with a Pierburg 2E. The golfs also had a similar set-up and I believe also some Audi 100's. This is a picture of the set up. This is the carb slightly rasied off the inlet. Unfortunately I failed to capture both vacuum ports clearly . But one can be traced from my thumb. along the accelerator pump and goes to the port on the front of the carb. The unused port is hiding behind the pipe running to the waxstat and is parallel to the front port (ie pointing toward left wheel). Both ports seems to run off the primary venturi. Here is the vacuum diagram for a Pierburg 2e2 (slightly different carb) from the VAG SSP docs. You can see vac line marked C that goes to an actuator for the auto box. But this is for a transverse golf engine Tonight I plugged the rear unused port. The car starts but runs richer than ever to the point that the unburnt fuel is dripping out of the exhaust. I need to wait for the new pull down but I am considering opening up the throttle screw on the secondary venturi to allow the engine to get more air as I had closed it up as specced in the Haynes book. Last edited by tram-man; 19-01-15 at 10:18 PM.

20-01-15, 07:03 AM	#6
andya Senior Member Classic Audi Club Member Join Date: Aug 2010 Location: Hampshire Posts: 1,149	My old 1986 base coupe b2 was a 4 cylinder 1.8 ds engine. It also had the pierburg carb, but im afraid I lost my patience with it and replaced it with a reliable and easy to work on weber -though I realise you didnt want to hear that! http://vwa1.dadoghouse.com/?p=16 Found this - a pierburg manual to download. Good luck __________________ 1985 Coupe Quattro 1986 Coupe 1.8 weber carb 1987 Coupe 2.2 GT

20-01-15, 11:55 AM	#8
andya Senior Member Classic Audi Club Member Join Date: Aug 2010 Location: Hampshire Posts: 1,149	Hi No sadly when I wrote my car off, I sold the weber off separately and the old pierburg I donated to someone on here for free! Can't remember who mind you? __________________ 1985 Coupe Quattro 1986 Coupe 1.8 weber carb 1987 Coupe 2.2 GT

20-01-15, 04:56 PM	#9
andya Senior Member Classic Audi Club Member Join Date: Aug 2010 Location: Hampshire Posts: 1,149	Just looked it up, my old pierburg went to BigT80 on here. He took it as spares. Might be worth contacting him via the pm system and see what his thoughts are. Regards __________________ 1985 Coupe Quattro 1986 Coupe 1.8 weber carb 1987 Coupe 2.2 GT

19-01-15, 11:11 PM	#4
vorsprung durch technik 4 ring whore! Classic Audi Club Member Join Date: Feb 2014 Location: Near Watford. Posts: 7,762	As far as i can see you haven't mentioned what engine you have.But going by the ref to the 80 CD sedan that will be a 1.9 5cly with engine code Wn from memory,i used to have an 80 CD saloon.Is that what you have? If thats the case these the carburettors fitted to these engines are great untill they go wrong and they always do.The seem to drift out of tune.Thats my experience of them having to take apart for a rebuild and every year or so take top half off and reset the floats with correct measurement. It sounds to me that your is on choke constantly. Damm i had the manual handy a few weeks ago and now cannot find it. I am wondering if you even have the correct carb fitted as it designation doesn't ring a bell to what i had on mine. But of course for different markets quite often different carbs/emissions used. Whats you engine??

20-01-15, 12:39 AM	#5
missfire making wooden things Classic Audi Club Member Join Date: Dec 2009 Location: cow land Posts: 8,156	Hi, don't know if it's any good but I used this site a bit when I had a B3 carb. Lots of diagrams with keys. Some pierburgs near the bottom of the page - http://www.gowerlee.dircon.co.uk/spares.html#pierburg

20-01-15, 07:25 AM	#7
tram-man Grown up member Classic Audi Club Member Join Date: Aug 2013 Location: Location: Location Posts: 37	Sorry, forgot to say explicitly that it is a 4 pot 1800. Thanks for the tips and links. Yes I believe my choke is wound closed too far. I have been trawling the web and they refer to an opening of 3mm for the choke. I closed it right down.... Andy, do you still have your Pierburg? If so, could you turn it over and see if the rear port (engine side) has a blanking tube? Stuart

25-01-15, 04:40 PM	#10
tram-man Grown up member Classic Audi Club Member Join Date: Aug 2013 Location: Location: Location Posts: 37	Well I have Fitted the carb with a new pull-down choke and Replaced the vacuum on the dizzy which was not holding vacuum well. Checked the wax stat which works and checked the resistance of all the ignition parts. Rechecked dynamic timing. So all the component parts work now and the car absolutely flys. I have just plugged the open port as I am now almost 100% convinced that this should have a plug (or is a take off for the econometer or automatic gearbox). I think the plug has always been missing or that the car has back fired and launched it somewhere. I have bought a vacuum tester (ebay 15quid) in order to set up the rest of the 2E. It still seems very rich ticking over (when warmed up) and I think the whole carb has been played with and I need to reset it. I have found a link thru this forum to a more detailed set-up of a pierburg 2e(2) which I found helpful. The Haynes coupe manual is very sketchy and doesn't cover the workings properly in the supplement at the back. It is not a link for the Audi carb but it gives a bit more basic info. http://www.clubgti.com/showthread.ph...urg-2e-problem What I am really after is an official Pierburg audi 80 90hp set-up manual. Or a VAG workshop manual covering the 2E for the audi application. On a steep learning but happy to help anybody with similar B2 woes