was driving home the other night, and the car cut out, i restarted her, tickes over perfectly fine, but if you press and hold the accelerator the revvs will rise, then you will hear the engine "breathing" then the engine dies, like as if there is no fuel left. in the end i had to push the car home half a mile. yet again i started it up in morning, ticked over fine, drove down the road, then did the same again. checked all engine and ignition timing - all ok. took the four jets on the top of the carb, blew them all out - they were clean as a whissle. any ideas of what it could be as i despratly need the car to get to work. Ps. carb is a weber 32/34, manual choke, no warm air intake and no electronic gadgitary. this engine has been running perfectly since last altered several months ago.
this exact same thing happened to me, i was stuck for about half an hour. i have no idea what was wrong, but its fine now
Bit of a wild theory for you, but I had similar symptoms to this once. I fecked about for hours checking all sorts of stuff, and finally found that the new (fitted by a garage that day) inline fuel filter had a split in the plastic seam weld which was letting in air, so removing the necessary suction to pull more than a trickle of fuel out of the tank. If you've had a new one of these fitted lately, have a look...
i think its ok, but for the sake of 39p i'll replace it, was also thinking it could be a weak fuel pump. but there is no way that the carb would empty the swirl pot and float chamber with one revv, i was hoping it was carb icing, but its not cold enough, and it still does it when engine is hot.
carb icing is more caused by moisture in the air rather than cold temps per se. Last time my carb heater packed up it was a summer's evening (about 10C I would guess) but quite humid. what happens is that the fuel evaporating into the airstream in the carb removes heat energy from the air so cooling the airstream. this causes water vapour in the airstream to condense into liquid water which, if the air is cooled enough (ie engine under load), can freeze. So if the air is cool (or cold of course), humid and you're accelerating or driving up a long hill then your carb heater is what is stopping your car from losing power
when the car cuts out, pop the fuel feed line off the carb and get someone to crank the engine over briefly. Be very carefull while doing this! If you can avoid doing it when the engine is hot and point the fuel line into a container or something. If it takes a while of engine cranking before fuel comes thru you have a weak fuel pump
i tried that earlier! my fuel pump is fine its squirtin out fuel like a good un i can press the pedal lightly and bring the revs to 1000-2000ish and hold it there then it will slowly die down and stall. i dont understand whats wrong because its been fine since i bought it a month or so ago
yea i solved it in the end, 3 times i stropped the carb and cleaned it out with thinners. each time it improved, but still had down falls, spluttering ect. so thinners and a straw/blow off valve is the answer. also renewed the filter on the fuel line.
cheers for the info dude, did u strip the carb totally all the way down? and what kind of thinners did you use?
before stripping it, try empting half a tin of careb cleaner into and around the carb while its running, hold the revs up so it dont stall. Then look at your vac hoses etc, chuck another filter on there and see how it goes. A long shot but try it with the petrol cap off, I've heard that the tank can form a vacuum and prevent fuel delivery, but I've never seen it myself. Stripping the carb down should be the last thing you try, check out my 2e2 FAQ as well! EZ_Pete mentioned watching the 3/4 point unit as well as it stalls, worth a look
i have read your FAQ well done for making that it helped alot! ill try the petrol cap thing. i dont think i will be able to keep it running with some carb cleaner in cos it stalls so bad but ill try
Just rev it with one hand on the throttle cable/spindle bit while spraying with the other (or get an assistant to sit in the driver's seat and keep the revs up. Watch you don't get carb-cleaner in your eyes, it tends to richochet; it stings, and probably does serious damage!
i stripped it all the way, all jets out, floats out, everything. mixture screw out. was just standard thinners, didn't really know you could get different types.
First frost is on the way, and as ever it's preceded by the carb-icing season. Make sure your carb heaters are working, and the hot air feed from the manifold is in good nick. If it still fails, then start thinking about the o-ring in the manifold!
i didnt do nothin to my carb since askin the questions cos i been busy... but belive it or not, the car is running fine. wtf!!
My car has started having a similar fault.... about the second week into September (once the cold mornings came), my 1.8gl mk2 would start up but if I took my foot off the accelerator she would stall. So I've checked the carb heater mounted on the front bottom and that was fine... All the air box is original and does have the hot air feed pipe from down near the manifold. The other day I dosed the carb and air box unit in carb cleaner (did get a black spray out the exhaust!), and that didn't cure it! so this weekend I was thinking I'll change all the vacuum hose's, when this morning on my way to work I was getting to the top of a hill in 4th and I was putting my foot down and not getting any where- then on the straight still no joy, dropped into 3rd and still was gradually loosing all power... I pulled into a lay-by and she stalled, I waited 5 mins or so and started her up and she was fine (bar the stalling when not accelerating). Does anybody no what could be causing this.... I'll probably be changing the vacuum hoses and the fuel filter? but I aint got a clue about carbs. oh a thought- could me changing between super unleaded and normal unleaded have anything to do with it??
sounds exactly like carb icing, have you checked the metal shroud on the exhaust manifold where the warm air hose fits is present and that the flap in the end of the airbox that directs the warm air opens when the engine is running?
classic icing that one, I am guessing that the warm air flap has seized on its spindle. Mine jams every year and WD40 sorts it out for the cold months...
Also worth giving the airbox thermostat a clean out. Even if the flap and diaphragm and all the vac plumbing is OK, if the thermostat isn't able to direct the vac towards the diaphragm that moves the flap, it won't work. See http://www.clubgti.com/forum/showthread.php?t=115460&highlight=mend+mk2 for details. Basically you need to get any oil/dirt out by squirting carb cleaner etc in one of the vac nipples, the one nearest the carb IIRC, with the other hose removed to allow it to drain out. After weeks of trying everything else, this finally sorted my icing probs. I was only able to narrow it down to this by fitting a temperature sensor in the airbox, so I could see what was/wasn't happening.
