Hello folks, I hope someone would be kind enough to give me a few pointers with this one, I'm still trying to figure out how everything fits together on my 1978 2ltr air cooled lump in my Bay. So the problem... it suffers from an intermittent loss of power, almost like I've run out of fuel, it won't keep the revs up and starts to back fire, and if I try to accelerate the revs just drop and the engine dies. Most of the time it's great, runs as sweet as a nut. It did this on my way back from Devon a month or so ago and again yesterday when i was coming back from a car show at Bognor Regis. Both times the fuel guage had just gone on to reserve, still showing full reserve though. So I managed to get it going again and filled up but it started to do it again after about a mile, then again after about 15 miles. Both times I wiggled a couple of wires around in the engine bay and hey presto off we went running fine again. I'm thinking this has to mean that it's electrical, of course, I've included a couple of pics of the cables in question, are they something to do with the HT feed to the coil? I'm thinking maybe if I have a bit of a dodgy connection somewhere it's just causing a weak voltage to the coil and then not enough at the plugs to give me some power when I let the clutch out? I'm a) trying to identify if I'm on the right track and b) after some pointers on what to check etc. Oh and when I wiggled the cables I can hear a 'click' coming from the engine somewhere, as though a relay or something has just kicked back in? The cables I'm talking about are the brown/copper coloured ones that go in to a V. Thanks - Simon.
Go on I'll bite then. Been waiting all afternoon for somebody else to to come in on this. First off check the fuel cut off solenoid - thin brown wire to the carb. There's also some others on the left hand carb too. Also check the supply to the coil is good as this comes off the same source as the solenoid. Then check the connection to the regulator top right. Looks like you've got some domestic wiring in there. No reason why it shouldn't work, but it does point to a potential bodger. I'm guilty of that myself. Then we can talk about your fuel tank if this doesn't work.
^^this Alternatively as was slightly touched on above. Rubbish in your tank that has been sucked past your inline fuel filter (you do have one right?) into your carb and in turn blocking jets or passages.
I am SO not an expert in VWs or electronics, or even mechanics, so feel free to take this with a pinch of salt I recently had almost exactly this problem, Wiggie was cutting out over speed bumps occasionally as well, and it all seemed to happen far less at higher speeds - at lower speeds I ended up stationary in rather short order and waiting varying lengths of time for at the time I knew not what before I could suddenly start again and all worked fine.... for a while. By running him while stationary and wiggling random wires until the same thing happened I tracked my issue down to a dodgy connector onto the ignition coil - replaced the old knackered spade connector for a better one with less wobbly connections to the wires and hey presto it all works fine again touchwood: ). I posted on the "what have you done to your bay today?" thread here, and Owen Snell said he'd had a similar issue with the negative spade on the coil as well. As I say, this is the sum total of my experience with an issue such as this, so it may or may not be relevant to you (and other people, please also say if you know it's not!), and your wires could be completely different ones leading to similar symptoms, but I'm so excited at actually potentially knowing something which might possibly maybe even vaguely be of help to someone for the first time ever that I just had to reply!
More ideas- centre wire on coil loose dropped out making it rough . And a self inflicted one I had . I fitted a fuel cutoff solenoid outside the engine bay both to prevent fuel dribbling from the carburettor and as a way of stopping fuel into the engine bay in general. The valve filled up with crud and stuck...In my case it would kill the engine but it could have stuck part open. I put the valve downstream from the filter and cleaned the valve. Check you havent got a semi hidden filter full of crud.
