Pierburg 2E. Starting Problems. 1.8EX Engine.

Good Morning All.

Symptoms are: Engine refuses to fire, or if it does, dies shortly after. If I pump the throttle 3 or 4 times before turning the key it'll start, revs will rise immediately to about 1500rpm for only a split second then dies. If I don't pump the throttle beforehand, it'll just turn over and not fire. No apparent fuel leaks anywhere, fuel is getting into the float chamber. You can see the fuel entering and leaving the fuel filter, so the fuel is going somewhere. I've replaced the diaphragm behind the accelerator pump unit because that was leaking. Gasket/riser block between the carb and manifold is fine, no leaks there. Electrical cable from the automatic choke cover is connected, all other wiring connected as should be. All vacuum hoses replaced and connected as should be. The part throttle channel heater is knackered and yet to be replaced (anyone know where I can buy one?), but don't see that being the problem. Wax stat. has been removed and tested and appears fine.

Everything in terms of ignition is spot on, although yet to check the timing, but car started and drove reasonably well when it was last driven a couple of years back, although it had a very fast idle that I'd hoped to sort once we can get the thing started. I also get an occasional back-fire through the carb when trying to start, and once even a flame exploding out through the carb with the airbox removed.

Replacing with a weber and a manual choke seems to be a bit of a cop-out and I'm trying to keep the car as stock as possible.

So, anyone have any ideas? I'm suspecting choke, but I'm at a bit of a loss. And a link to a Pierburg 2E manual would be great if anyone knows of one??

How old is the petrol in the fuel tank?

mark1gls said

How old is the petrol in the fuel tank?

Hi Mark.

New :-(

However, fuel gauge is reading empty (sure it worked before), but I did pour a few litres in there before. Can see fuel in the filter so it can't be a lack of fuel, no?

Petrol does go off after 12 months and the car won't run very well on old fuel that was what I was thinking… Have you looked inside the fuel tank, you can get access under the back seat to check the pick up is not getting blocked once the car is running or maybe try getting some fuel hose and a can of petrol and take the fuel from the can just before the fuel filter in the engine bay?
Have you looked at your spark plugs? Pumping the throttle before starting may just be coating them in lots of petrol remove them and give them a clean and check gaps.

Hi Mark.

Thanks for your comments…..all ignition parts are new and as I said it does fire after pumping the throttle several times , so I believe that its firing from the fuel pumped in from the accelorator pump but immediately dies when that fuel is spent and not getting fuel through the idle circuit.  Blocked idle circuit could be the culprit but how I rectify that is beyond me. Any ideas?

Sorry can't be much more help as I've not had any experience with the Pierburg  carb so can't help there.
My carb car had a Zenith carb and when it started to go wrong I took the easy opition and stuck on a Webber as it was my daily drive.
There should be some guilds on the web to rebuilding/cleaning out the Pierburg?

have a good read here, be sure to check everything top to bottom
http://www.vwgolfmk2.co.uk/forum/viewtopic.php?f=37&t=14917

to make sure the swirl pot isnt the issue bypass it and run the fuel feed direct to the carb see if that helps. if it does check you havent lost the restrictor on the fuel return

Hi John,

Thanks for your reply. The link is useful but doesn't seem to be answering my problem. Bypassed the swirlpot and same problem - fuel is defo getting to the carb.

I've made a video, showing that it starts (for a split second) after pumping the throttle then dies - also shows backfiring through the carb. Can I post videos on here?

Here's a video which hopefully explains my problem. 3-4 stabs of the pedal before turning the key and it starts (for a second) before dying. No pumping of the throttle beforehand and it refuses to start. Flames from the carb isn't normal, I'd guess.

- YouTube

is that a cold start? if so your choke flap is wide open so that would be where I would start looking

rubjonny said

is that a cold start? if so your choke flap is wide open so that would be where I would start looking

Yes, cold start…..cant start it to be able to get it hot.  

I agree, choke flap is wide open. I have adjusted this by turning the "screw" on the pull down unit, but it goes out of adjustment immediately. Does this suggest that the pull down unit is defective? And can they be replaced? And would this really stop my car from starting?

Also, the 3/4 point unit is extended approx. 18mm when cold, not the suggested 14.5mm. Could this be part of the problem, I can't see how this is adjusted :-(

No ideas, anyone, on this  

its the autochoke unit I would be looking at, the pulldown doesnt hold the flap shut rather it works the other way round and stops the flap from fully closing when the engien is running!

Thanks Rubjonny.

Took the choke housing off……and guess what? No bimetalic spring inside and also the white lever that connects to the bimetalic strip is broken. Anyone know where I can get parts for these carbs? Can only seem to find wax stats, gasket sets etc.

Obviously I'm going to start here, but strange that this could be causing the problems. Had been driving the car with this choke missing previously, so odd that it should suddenly refuse to start now. The car's in Spain so I guess the PO had choke problems and decided it wasn't needed here.

As you can see - definitely missing the spring:

I also did a compression test and got 187.5, 209, 170 and 197. Second attempt I got 182.5, 192.5, 177 and 190.  Squirted a bit of oil down each plug hole and got 205, 230, 215, 225 - so no leaing past the valves, I assume. What's your thoughts on these readings? It's a 1.8 EX engine. Obviously I had to do the test with the engine cold, since it refuses to start. 

was that with throttle wide open?

for 2e2 spares i would try to buy a complete unit from ebay/classifieds/scrappy then strip it down and check all the components as per my FAQ. then test the parts on the old carb and swap over workign parts if anythign is found to be duff

ahh, dammit!!! No, I forgot that the throttle had to be wide open. Maybe I should test again?

From what I read, my results are more or less OK - max. of 15% of each other. And I suppose that I should expect them to be higher when the engine is warm. Obviously I was unable to warm up the engine beforehand.

So, it looks like I'll be trawling the scrappies….

check again with throttle fully open before you worry, you wont have a true reading if the throttle was closed

Thanks Rubjonny.

Out of curiosity, how does the throttle being fully open make any difference to the reading?

Sorry if that's a stupid question, but it's not obvious for my limited brain :-(

allows the engine to suck in air easier, otherwise its got to squeeze past the tiny gap in the throttle/choke flap. which somehow it makes a difference, I'm not sure why but it does so do it

Makes sense, I suppose.

Thanks!!