hi guys. wondering if you can help me with a problem. my golf seems to be very hesitant when pulling away and driving along steadily then accelerating, so far ive changed the waxstat, adjust the cams correctly for cold idle, auto choke is working as it should, pdu also checked and found to be fine, 4 point unit works correctly, and accelerator pump working fine, however when starting from cold, it will start and run fine, but when putting it in gear (mines a 1.6 auto) it stalls immediately, or coughs and splutters until it suddenly picks up again, it feels similar to whats described as carb icing, however im confident it is actually flooding itself. when driving along at a steady speed and increasing throttle it will bog down and then pick up again, often kicking down into 2nd gear. as the engine warms up to operating temp the problem is reduced only to bogging down when moving, pulling away seems ok, occasionally will bog but not cut out like when cold. i changed spark plugs, leads, dizzi cap and rotor arm yesterday to see if it might be that but the problem persists, the old plugs were coated in thick black soot so its definitely overfueling. i have adjusted the mixture screw as it was running a bit rich but if i do it any more it will cut out for not having enough fuel to idle correctly, yet when driving it will still bog down, even more so in fact if the mixture is lean. i noticed when stopping also after a drive and turning the engine off the carb floods itself, i took some pics which are difficult to see as its just a camera phone. before starting, as it should be: after a drive, difficult to see but both chambers are full of petrol, this eventually leaks into the manifold over about 10 mins, but if you try and start it again it struggles for a few turns, then a puff of black smoke as it ignites: any help would be massively appreciated as im currently getting 21 mpg and i need to fill up... again cheers Stu
First thing I'd say is that overfuelling/flooding is not necessarily inconsistent with carb icing. I can't explain exactly why, but the last time I had a bout of icing, I also noticed that the air/fuel mixture went fully rich (I have an intake air temperature sensor just above the carb, and a narrow-band oxygen sensor in the exhaust. When the car started misbehaving I noticed that the air temp was much lower than it should be, and the O2 sensor voltage was maxed out, highest voltage ever seen). Easy to imagine that icing causes fuel starvation, but actually it may be more like air starvation. So check that your incoming air is being thermostatically controlled correctly, and make sure the bypass heater (part-throttle channel heaater) is heating. Athough your carb looks like it has had the benefit of some carb cleaner, there are a few critical areas that it would be worth checking, namely the air corrector jets. These are important during normal running, and at shut-down or even slow-down, to prevent siphoning of fuel in excess of 'real demand'. The primary barrel has two corrector orifices, marked blue (idle) and red (main). The idle one is the vertical slot, or pair of holes near the base of the little tube that houses the mixture/CO adjustment screw (above the idle jet/emulsion tube). The main jet air corrector is drilled through from the primary barrel, probably so that the choke flap can negate it during cold-start. The first pic shows the locations of all four air correctors, the two mentioned above, and the secondary barrel main jet corrector (yellow arrow) and secondary 'idle' corrector with green arrow. Second pic is a cut-down of the top of a 2e2, showing where the primary main air corrector drilling goes. You can just make out the teeny orifice visible as a black circle in the side of the brass jet emulsion tube). Again, pointed to by the red arrow. All these holes need to be clear. The secondary barrel ones are straightforward, as they can be 'poked' with suitably sized wire, after a directed hosing with carb cleaner. For the primary idle corrector, it's possibly worth removing the mixture screw tube, for easier access to its slot, and the hole in the top of the idle emulsion tube beneath. You seem to have adjustability via the mixture screw, indicating that this area can't be too blocked up though. For the primary main air corrector, it's going to be a challenge to clean or check with certainty, but definitely attempt to fire a beam of carb cleaner into that drilling, and maybe poke around with a bit of thin wire, hoping to feel it go through that teeny hole into the emulsion tube. Edit: arrow in 2nd image and rotation clockwise should happen when photbucket behaves.
thanks pete, im going to take the carb off tomorrow to get a proper look at everything and fully clean it. want to make sure all the channels and hoses are clear. i dont really want to strip it fully as i dont have a rebuild kit yet. any ideas where i can get one? im hoping to get a spare carb to rebuild and then just swap them over. 1 development i made today though was, looking in the following pic, the plate that has the non adjustable screw that acts upon the 3/4 point unit has a small phillips head screw on it. this seems to be a cam that acts upon a lever going to the accelerator pump, this was at its highest setting, which therefore had a long stoke on the accelerator pump (pumping more fuel in). i figured if i reduce the stroke length by adjust the cam to its lowest setting, then the effect on the accelerator pump will not squirt so much fuel in and aid the bogging down effect when the car is moving. this worked wonderfully when the engine is up to temp, only hesitating a couple of times when accelerating whilst moving on a 30 minute driving in urban traffic however, the idle is a bit rough now and ive noticed an occasional misfire at idle, maybe its too lean? left it to cool down and started up again, it certainly doesnt run as smoothly from cold and the problem of wanting to cut out when pulling away and driving is almost worse was it a good idea to make this adjustment or should i put it back? so i got my multimeter out just to make sure all the electrical points were giving power, the ttv is getting 11.5v (with ign on but not running) auto choke is getting power, cant remember the reading though. the throttle body heater was also getting power 5v iirc, and seems to have continuity, but i did find an extra part ive no idea what it is though, i forgot to get a pic so will do it in the morning but its like a 12/13mm nut with an electrical connection coming out of it, mounted directly next to the wax stat, it neither got power or showed continuity, any ideas what it might be? i will update early as i can with lots of pics in the morning once ive got the carb off to show all these areas cheers
Not sure on the accel pump adjustment, can't see why it would affect idle, unless you accidentally bent that plate with the screw while you were at it? Throttle body heater should get exactly the same voltage as the TTV, as they are wired in parallel. Your extra mystery part with the large brass hex is a thermoswitch that turns the rad fan on if the carb gets too hot after shutdown, through engine-bay heatsoak. Not essential at the best of times. If you ground the wire that goes to it, within a few minutes of the engine having been run, it should kick the rad fan into action. Mind your fingers/hands if you test this! If you disconnect the accelerator cable from the carb tomorrow, take a pic of how it looks at the bracket first, as it's easy to put it back on too loose or too tight and end up with an extra problem. I got my rebuild kit from 'Fuel Parts UK' but dunno if they still exist or stock the kit. German ebay always has some, but not ever so cheap.
Thanks again Pete, I've been called into work tomorrow now and have the joy of leaving at 5.30am so I guess this will have to wait until Friday morning for me to strip down. I'll note any problems that occur and include in my next post with the pics. Cheers
hello. right, had a manic weekend so only just getting round to sorting this. got the carb off this morning, here are a couple of pics from the bottom (right side is front) from the top now, whilst its off i want to set it up properly, ie choke gaps etc, so in the first pic, the the position of the throttle flap in the right place, as it is not fully closed? secondly the choke flap, that is currently its closed position, is that too big? what should it be? ive also checked the fuel ways you suggested pete, they all seem clear. ive got to change the manifold mounting flange as the old one is pretty poor, and i once again checked the current of all the electrical components, the TTV got 12v, so did the auto choke and throttle body heater. one part i hadnt checked before was the inlet manifold heater/hedgehog, this had nothing whatsoever going to it. i hadnt started the car so it was all cold, does this only work when the car is running or should it also have power with ignition on and if so how much? ill trace the wire to see if it has continuity too cheers stu
ive also noticed after ive given it a proper clean that on the top and side it says pierburg 2e, you can actually see this in the last pic. does this mean that its not a 2e2 or do al the 2e series just have this stamp on them?
ive now traced the wire for the hedgehog back, it goes to the back of the fuse box, in the very top right corner if youre looking at it from behind, the wire is showing continuity, and with the ignition on im getting roughly .3 volts from the terminal it connects to. does this go to a solenoid or fuse? whilst i was down there i noticed that fuses 5 and 6 were missing too, 6 is the fog lights which i dont have, 5 is the fuel pump, is this normal not to have one on a driver? if not what rating fuse should i have? cheers
Starting from your last question: fuel pump on carbed models is mechanical, not electric, so no fuse. There is a relay that fires up the hedgehog (or not) depending on the temperature of a thermoswitch in the front coolant flange. Depending on year of manufacture the hedgehog relay will be either in position 12 (bottom right corner) of the fusebox (post 1990) or position 2 if pre 1990. The relay has number 1 written on its end facing outwards. Thermoswitch is red I think, and should conduct below 55C approx., and not conduct above. Regarding your pics, and primary throttle and choke flap angles: With engine off, the 3-point unit's actuator is at maximum extension, and holds the primary throttle open a fair bit to facilitate starting without needing accelerator pedal input; so that looks normal. Choke flap angle is extremely temperature dependent. If that carb had been indoors for a while before the pic was taken, it is likely to be at a correct angle. Pop it outside for half an hour and you should see it close up completely.
the pic was taken soon as i got the carb indoors so completely cold, thats as far closed as it would go, ive twisted the autochoke unit now so its closed completely at cold, is that correct? i have a pre 90 car so the number 1 relay is located in slot 2, ive tested the relay, and it clicks, however power is still not recieved at the terminal the wire going to the hedgehog connects to. i removed the relay and just put a paper clip into its place in the correct slots and it now gets 12v all the way to the connector of the hedgehog. so is this just a faulty relay not letting the current through? im hoping that this should be the only problem for the poor running. cheers
There's a couple of lines scratched into the autochoke housing and the bit it bolts onto, just next to where the wire clip attaches which holds the airbox onto the carb, these should line up when the autochoke is correctly orientated, I'll see if I can dig out a pic. Sounds like the contacts of your hedgehog relay may have burned out. Or there's a bad connection where the 'output' wire leaves the fusebox. Water leaks can often corrode fusebox pins in that corner. Rather blurry pic, but should give you the idea: Don't worry if you need to have it slightly off these marks to get it where you want, but do remember that at room temperature it should be slightly open. I think below about 15C I'd expect it to be closed, or almost there.
ive lined up the 2 slots on the autochoke unit, looks like they were in the wrong place to start with, too far anticlockwise, so more open than it should of been. i'll take a trip to gsf then and get a new relay as i need a new flange still, if they stock them, if not then vw, im sure they cant be much
right, got the flange, the old one looked well past it, the relay has to wait till tomorrow as it isnt in stock. now ive put it back together, but cannot get the thing to run at all now?!! it starts up then imediately cuts out, any suggestions?
Double check that all your electrical connections are OK. Check you got all the vac lines that were disconnected back in their correct places. When you checked the pulldown unit's function, did you also check that the vac hose going from the base of the front of the carb to its lower port was not leaky/cracked? It looks OK in your pics above, but if it was leaking, it may explain why the choke-flap was adjusted to be 'pre-open', and therefore why you're having trouble having adjusted it back to how it should be.
Try pumping the go pedal once or twice then starting it up and keeping your foot down a bit to keep the revs up. You may need do to this a couple of times before it idles. This will either get it going or flood it! I do this with mine as I ripped out the auto choke and waxstat as they were being unreliable. I now do this every morning and even in this cold weather it idles after 2 or 3 goes and then I leave it warming up for a few minutes before I set off. It's not ideal but it's reliable.
I have tried pumping it and flooring it, they do seem to improve it a little bit but it still bogs down. I'm on my way back from work now so will pick up the new relay to see if that does anything, if not I'm taking it to my friend who's a vag mechanic and will see if advancing the timing will do anything.
Well having changed the relay it seems to be much much better today. It still bogged a little from cold but not as bad as before, and when driving it seemed to be fine, still going to try the advance and make sure that the fuel mixture is correct and hopefully that should be it happy days
So after leaving the car over night to cool off properly, this morning the old girl would not start, argghhh!!! Richened it up a bit to get it going, and got to my friends to get the advance set up, it was actually 8 degrees out!!! No wonder it was rough, that was set correctly and then corrected the fuel mixture, turns out it was actually too lean, and somehow the engine was compensating and putting too much fuel in as the reading gave loads of unburnt fuel in the exhaust. So that was put right, and she's running like a beaut still need to check it when it's cold too to make sure it runs well too. Then well see how well the fuel consumption is going, lol.
