Hi i was wondering if anyone knows what is up with my car? when it starts, like many golfs it revs high, then dies down. when its cold it drives fine, however when its been running for about 15 mins the engine goes crazy! irl put my foot down and nothing will happen, as if its a delayed action, then the car will judder forward and accelerate with about half the power, it feels as if there is a restriction on the engine. Its really annoying as i love my car and after several trips to the garage and a few hundred pounds[:^(] its still the same!!! arrrgh CAN ANYONE HELP???????? ohh its a mk2 golf Driver 1.6 carb engine with no modifications to the engine.
Worse when it's cold damp weather? Sounds awfully like carb icing. Do a search for any number of threads on that topic. Things to look for are the pipe from the shroud round the exhaust manifold being in place, the flap in the entry to the airbox being free to move, this flap staying 'up' when it's cold out, carburettor earth being present and in good condition (brown wire carb-to-valve cover stud), and the heater next to the idle jet getting hot... for starters Pete
No. It's usually melted within a couple of minutes of stopping the engine (or it stopping all on its own). Basically the carburettor acts a bit like a fridge, with the fuel as the refrigerant coming out of the idle jet and evaporating in the airstream going by. This takes a lot of heat out of that airstream, and everything around it. If there's any significant amount of moisture in the air, it'll condense, and then freeze onto vital parts of your carb like the throttle plate and around the idle jet. Warm (20C) air as should be supplied within a few minutes of starting the car (iff the warm-air feed is in place, and the thermostat on the side of the airbox is working, and the flap's not stuck- three big ifs) will help to prevent this. Also the heater that warms the idle jet all the time the ignition's on will be very important (remove airbox completely, look at front of carb low down, heater is a black cylinder about 15mm dia with one black wire coming out of it). With ignition on you should feel warmth round this, or measure volts/ohms/amps if you have the means (4.5 amps when cold is a great figure to see, decreasing as it warms up). Lack of warm air most likely prob, this heater next to check, then a few other things... Best of luck, Pete
Well the pipe that connects from the air intake pipe to the back of the engine ( to a heat shield, i think manifold?) was broken for a little while and not connected 100%. However at the time not knowing anything about it askd the garage to change it. but 'it wont make a difference to anything'. A stupid question most proberly, but what is the idle jet? the throttle plate is the flap in the middle that open and closes with the accerlrator? and one final question, is the thermostat where the two vacume pipes go into the airbox where the filter is?? What other things would you suggest to help cure it? Thanks alot btw, this has been a great help. Wow im starting to understand my engine! yay! Cheers
Bum! I just typed out a reply to these questions, and all of a sudden it vanished from in front of my eyes! Anyway: the warm air pipe is needed, only a very few people seem to manage without, for reasons I don't understand. The idle jet is down at the 'front bottom' (ahem) of the inside of the primary venturi, down near the primary throttle plate. It supplies a fuel/air emulsion into the gap between the slightly-open throttle and the wall of the venturi. Prone to icing up because of the small size of this gap. The idle jet is used all the time, but supplemented by other jets at wider throttle openings and higher engine loads. The airbox thermostat is the bit you describe. Can tend to clog up with oil and crap, can be cleaned out easily, restoring function. Search for "Mend your Mk2 driver's airbox thermostat" if you don't mind reading more of my rantings... Another thing that could affect icing/cold-weather running is the so-called "hedgehog" aka inlet manifold pre-heater. It's a powerful heater that sits right under the carb, with lots of vertical prongs to help shed the heat it generates into the fuel/air mix coming down into the manifold. This helps the fuel to be fully vapourised before getting into your cylinders, improving running and efficiency. Can again be fixed, in my experience, if not working; without even removing it from the car which is a manifold off job. (But you may need to take the manifold off anyway at some point, to fix the 'coolant channel o-ring problem, which you are also likely to have). Enough for now?! Pete
I found with mine that when putting your foot down as it's juddering there was a delay of a couple of seconds before the car suddenly took off. I assume this was the vacuum increasing until the second choke opened. This has got to be a first - a number of posts without a mention of the 'w' word....
Weber carbs are great for MK2 Drivers (I expect, though I've never tried one) There you go gbk, that's that out of the way Pete
they're great for people who have given up on the 2e2, and who like to spend more money on petrol Better for tuning tho
One thing I forgot... 8olf-blu: I forgot to say, just about the most common reason for the warm-air feed system (and lots of other Pierburg systems) not working as intended is vacuum leaks. For the warm-air feed there's a thin transparent hard plastic pipe coming from the back of the carb to the airbox thermostat, and another going from there to the flap-mechanism diaphragm. These pipes themselves are usually OK, but the short lengths of flexible rubber hose that couple them at their destinations are prone to degradation, cracking, and leaking. Replacement advised. GSF sell something that'll do for about a pound or two per metre, I'm still hoping to find some stuff that's more like the Pierburg original vac piping, as it's more flexible, and seems to seal better...
Thanks alot, ive got a few things to check now. all of the pipes have been changed on the vacume (i made sure the garage changed them) also ive had a new fuel filter fitted, a bloody massive one actualy! is there any threads on how to fix the heater without actually removing it? and im going to look for how to de-clog the thermostat. ive taken a pic of the carb, dunno if anyone can see anything major? prob not tho!
Useful picture. Can't see where the carb earth wire is going to (brown wire LHS of carb)[Edit: yes I can, it's going to the right spot, but looks as if it's just about to break off], it needs to be connected to the engine, rocker cover stud, and give all connections a whizz with fine emery, then a drop of vaseline to keep moisture at bay. Without this connection, the heater by the idle jet, and the choke heater don't work at all. The heater by the idle jet is invisible, below the thing at the front with a white connector housing (which is an overtemperature sensor). The Hedgehog heater has a thick red wire coming out of it under the inlet manifold, with an inline connection that could probably do with a clean. What makes this one fail, I believe, is actually it's ground return connection corroding. This is only via its 3 mounting bolts (two of which are reasonably accessible) onto the manifold; then the mounting bolts from the manifold onto the head. As these bolts are all steel, and the heads against/into the aluminium manifold (or corroded cover of the hedgehog), they suffer electrolytic corrosion, impeding the (big) current flow that this heater initially needs. Loosening a few bolts, cleaning, vaseline, restoration of function. Check it gets 12V+ with ignition on, at the inline connection, and measure its resistance from feed to ground (disconnected) before bothering with this, should be less than 1 ohm, believe it or not. Current is too high for most meters to measure in series. There may be a current path through the manifold gasket (it has a metal core) too, but no-one has confirmed this, and I don't know whether gaskets ever do this? Your sealing ring between airbox and carb looks to be doing a poor job, cheap to replace. You are leaking some coolant in various places, not too serious, seriously common. Good luck, Pete
Thanks alot its given me some work to do. just gota hope its all good now! But can the pierburg carb be tuned at all??
not really, by tuning I mean replacing jets etc, not many places will do it on a 2e2 if any! Webbers are much easier to find parts for. Saying that the 2e2 is still a pretty flexible unit, guy on the 'other' forum ran his 1.6 with a GTI head, zaust cam etc all on the std 2e2 no bother at all!
is it work getting a webber then? i just missed one on ebay for 54!! a little gutted but neway! Are they more reliable, less prone to icing, et Didnt realise you colud do that!
They're less complicated and newer so are more reliable for these reasons. BUT people still have problems with them (esp. second hand ones), new ones cost 150+ and they are still prone to icing (some say more so). Kits are available for reconditioning pierburgs (see webcon.com) and anyway, getting your pierburg going is more fun!
So they're not that beneficial, and i must admit i do like the idea of fixing it myself as the garage cnt find out what it is?
