I'm personally half way through this topic myself. I'm £300 in to my carb on the Jetta. we have all been aware for years the peirburg is trouble. How ever after chatting with a couple of different mechanics. One that worked a lot on these carbs while working at a karmann restoration place "thou not strictly just them". Well he reassured me that getting a full rebuild kit, ultra sonic cleaner on the parts. it would be fine an working like new. That was true for all of 5 mins really. I've been back and forth a few times having it adjusted, as the idle and auto choke just love doing there own thing after a couple of hundred miles.
Talking again in recent times with him, Has now said if it plays up again just chuck a webber at it, or start the whole process again this time paying for the complete service to be carried out. Which after investing over half the value of a new webber. well you can guess its a bitter pill to swallow.
So long story short. I knew them carbs was a pain, we all know there a pain. I'm 300 deep on the carb now. Meaning the actual end bill, will now be £1000 if I act now. How ever I don't do mega miles, MOT in October, I may just wait
But I must add. I'm not a professional, I may of not cleaned the carb enough, I may of not done the carb rebuild correctly. There for I may well be the cause of the issues afterward the event "thou identical still". My story certainly is not the same as both mechanics claimed, as they both said a rebuild, ultra sonic clean, will cure it
But needless to say, I'm not investing any more money or time on the pierburg
Hi. I'm less familiar with the carb in the 1.3l, but there are some useful videos on how to rebuild the stock carb, and there are gaskets sets available. Its a lot simpler than the one in the 1.6! If its sat for 10 years, I would expect the carb to be full of crap, so its worth at least taking the top off it, and giving it a good clean with carb cleaner and blasting through all the passages with compressed air. If you dont have a compressor, just buy an aerosol of compressed air off amazon.
Not sure which one you need to replace. I replaced the one on top nearest the cylinder head, which was a grey one, and I had to buy it off ebay, cause I couldn't find it anywhere else. The grey one goes to the choke. The other one on top goes to the hedgehog, and I've not idea what the one below is for. I have a driver as well.
No problem. I spent a lot of time doing research on the Pierburg, and ended up stripping mine (the one in the video), to clean it. The video explains the various parts of the carb, and how they work. There are other videos as well. If you have a manual choke that gets rid of one potential source of trouble, i.e. the mixture. However, the idle will still be set by the three point unit, and the waxstat, neither of which are controlled by the choke cable, which explains why adjusting the choke does nothing. There are two electric connections on the back of the carb, the solenoid, which when activated stops the three point unit fully retracting (via the vacuum hoses), and the thermo time value, its only job being to allow the engine to rev higher (about 2k for up to 30s), when you first start it up, again by adjusting the vacuum in the 3 point unit. If you do the checks above, you should hopefully get to the bottom of it.
Does it have the original Pierburg carb, or a weber?
I'll assume it has the original. The Pierburg carb is a fussy carb and look very complex on first appearance, but you can get your head round it with the help of some you tube videos. If you have sorted the rubber mount, then the next thing I would check is the vacuum hoses behind the carb for splits. I prefer good fitting silicone hose cause it lasts longer. When you start the engine from cold, the idle is initially set by the 3 point unit on the left hand side, then it drops after a few seconds (up to 30s), and the idle is controlled by the waxstat. The waxstat as it warms up causes an arm to turn causing the idle to drop. If you remove it and find wax or coolant is leaking out of it, its knackered and needs replaced (assuming you can find one). In my experience, they are slow to react causing the idle to stay higher than you need for a quite a while. But it has no affect on the mixture, just the idle speed.
The vacuum hoses control the 3 point unit only. There is a solenoid on the carb that should click when you turn the ignition on, if it doesn't the 3 point unit will retract fully and it wont idle. You can test it by putting 12v through it. The choke is on the top of the carb. It controls the mixture only. It has a 12v wire feed, but its also controlled by the coolant. The 12v feed comes from the grey thermo switch on the top hose. Next to the head. When the engine is cold you should get 12v from the wire that goes to the fuse box, and from the thermo switch to the carb. You also need to check that the carb is earthed. If not the electric feed to the choke wont work. This is important, as it causes the choke to back off whilst the coolant is still cold. A simple check is to remove the air box and switch the ignition but not start the engine. After a minute you should notice the choke flap starting to open. If the choke will only back off once the coolant pipes get hot it will run far too rich when cold and cause the carb to flood and it bogs down the car, giving very rough running.
First of all, does it have the original Pierburg 2E2 Carb? These get a lot of stick, but once you get your head round how it works its not that bad. There are various you tube videos that explain how it works and what you need to check. I recommend you view them first. In terms of what's wrong with it, it could be one of the following. - The vacuum hoses at the back of the carb are split. - The 3 point unit is not working properly (possibly because of the hoses or the diaphram inside has gone) - The waxstat is faulty - The linkage between the waxstat and the throttle arm needs adjusted - The rubber mount is split
The fact that the engine runs on suggests to me the throttle arm is not going to the off position (controlled by the 3 point unit), so I'd check the hoses first. https://www.youtube.com/watch?v=taTBdkrQouI
I note no one else has replied, so I thought I would. First of all, if the car is driving fine, and passing the emissions test in the MOT, I wouldn't mess with the mixture. My only experience with problems with this carb (in a polo) is the choke pull down unit can fail, causing it to stall on a cold day, when running on the choke and pulling up at a junction. You can check if the pull down unit is holding a vacuum by sucking on the hose to it. As for the smell, have you checked the fuel line connections at the top of the tank, by removing the inspection cover in the boot? This potentially cause smells. Also the breather tube of the petrol tank in the wheel arch? I dropped my tank down to underseal above it and found the breather hose clip had rusted away, so worth a check. I would also check the filler cap seal. For the smell to come from the engine bay, the leak would have to be pretty bad, ie obvious.
I doubt the relay for the horn has anything to do with the fog lights, as that will be a separate circuit. Again, you can only chase down these problems using a wiring diagram to check all the relevant wires and circuits. If you have jumped the horn relay, and the wiring connections are all good, you probably need a new relay. As for 11v on the fog lights, in my experience you do get some voltage drop on the circuits, but that would not be enough to prevent the light from working, it would just not be as bright.
Normally when you get an air leak with a carb it will run, but it will not idle, as the extra air being sucked in means its not getting enough fuel. But it will still run if you keep the revs up higher with the throttle. That does not sound like your symptoms to me, unless I'm misunderstanding. If it will run at idle but wont get passed 20mph, that suggests a lack of fuel, for example a blockage, or a tired fuel pump resulting in the float bowl being half empty. Another thought is there some crap has got into the carb and is blocking the jets up. I'm assuming its running smooth and it isn't an electrical issues (duff dizzy cap, bad coil, lead or plug etc). An extra thought, make sure the vacuum hose is not split.
While these don't all come under the heading 'Engine & Gearbox', I hope you'll be OK with me listing them here. The vehicle is a 1990 Mk2 Driver (1.6 petrol).
My mechanic's advisories state:
1. Dipstick tube broken 2. Coolant flange on head has small leak 3. Slight leak from gearbox 4. Play in both front top mounts
What is involved in remedying these issues, so that I can plan ahead for mechanic time if necessary, being very much of a newbie with mechanics etc?
1. Metal tube or plastic? You can get the plastic piece online from many suppliers. The metal tube is unlikely to break 2. Will need a fresh seal/o ring. Easy fix, but will need to drain the coolant a bit first 3. depends where its leaking from, if its only slight I'd ignore it. 4. They always have some play when the weight is off the suspension. Not expensive to replace but I'd only do it if they are really worn out, and its not just the usual bit of play, otherwise changing them wont make any difference.
Your only option is to use the wiring diagram from the Haynes manual and check all the connections for faults using a multi meter. I would be checking for obvious signs of corrosion, for example at the main connection for the fan, as they tend to get corroded with age, and broken wires.
Cam will drop in, GTi manifold will fit. I went straight to a 4 into 1 stainless manifold on mine, but would recommend adding a heat shield for the steering column boot if you do that. The exhaust I put on was GTi manifold back, with the gl back box to give single pipe, so no need to cut the rear valance.
You can move to a GTi dizzy to make it run better as well
Yes you can add vented discs just make sure you buy the thinner pads
Thanks. Really hard to find a Mk2 GTi downpipe these days, but I've read online I could fit the Mk3 Gti/Corrado downpipe, and use a cat delete pipe to connect it to the stock exhaust. I now have all the exhaust sections, except the downpipe, so I need to track one down.
