Please help someone!!
Ive just changed my 2E2 pieberg carb to a manual choke weber which when first ran is spot one but when driving to work or driving home after about 30ish minutes the car struggles to rev. It will sit at idle but seems to cough! when reved. Ive read a bit about carb icing and found my heat despertion plate was missing so i fitted one with the tube to the air box but icing is still happening.
Im pulling my hair out now as i work for an Audi dealer and even the old skool techs are stumped!
Ive only owned the car for a couple of weeks and changed the carb as the 2E2 was rubbish!!
The weber is a second hand item but was told it came off an 1800 (which mine is) so i cam only presume the jets are fine. They have 155 stamped on them.
Any help would be fantastic because im a huge Mk1 Golf fan and was hoping this Mk2 would catch me to.
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dubbadub
The typical case of carb icing happens after a sustained constant speed run - a dual-carriageway for example. Switching-off and just leaving things alone for five minutes should let heat-soak clear the problem - until the next time. Does that fit with your experience? If not; try removing the petrol filler cap next time it's doing it.
There should be a vacuum-operated valve in the airbox's intake that diverts cold to warm air; are all it's plastic vacuum pipes present and correct and is the thermo-valve [mounted inside the air filter] working?
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What arrangements have you in place for controlling the air temperature entering the air filter housing? I'm not familiar with the golf set-up but my 1983 Passat GL5 suffered carburettor icing in just the circumstances you describe. I eventually discovered that crankcase fumes were condensing on and clogging the vacuum control unit within the air filter housing, resulting in the air control flap only drawing cold air from the front of the car and no pre-warmed air from around the exhaust. I rigged up a separator to reduce the amount of oil vapour in the fumes entering the air filter which stopped the problem.
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Ive checked all pipes and changed a few that seemed to be dodgy so air flow is fine as far as i can tell and yes it is on motor way driving.
The only thing im not sure about is on the back of the weber carb was a small pipe which went nowhere so i changed it to one that came off the pieberg which connects it to the air box(beside another pipe which goes to the front of the air box)
Il start from day day one! are we sitting comfy?
My mate bought the golf off ebay, it would stall at stand still after a run i beliveve this to be the wax stat, he then went to fit twin webers so stripped off the carb and intake manifold.
He then lost intrest as he does with most cars so i bought it off him but from day one it would rev well over 2000 with the 2e2 carb, i had it set up at work (Audi dealer) which was good for a couple of days but then went crazy due to the auto choke. That was when i went to the weber carb which is icing up.
I know the weather is cold at the mo but surly the hot air feed pipe from the manifold would cure the icing? unless its the air box control unit thingy!
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My bro fitted a weber to his Jetta, unlike the OE carb the weber did'nt have a return to the tank, but had a separate T piece. The car would'nt rev so we put a restriction in the return to encourage petrol into the float chamber. Try clamping the tank return with a pair of pliers and seeing if the car will rev.
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The proper "T" piece should have a restrictor in one of it's legs-this restrictor should be in the leg going to the return line.ie.the supply and the carb line should not be restricted.
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The proper "T" piece should have a restrictor in one of it's legs-this restrictor should be in the leg going to the return line.ie.the supply and the carb line should not be restricted.
My bro's was just a straight T, no restriction, we made a clamp for the return hose and the car ran happily for the next 2 years until tin worms ate it ;O)
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"I know the weather is cold at the mo but surly the hot air feed pipe from the manifold would cure the icing? unless its the air box control unit thingy!"
Just make sure the flap is actually operating to admit hot air to the carb. I had a Ford Fiesta with similar symptoms, and it was a problem with the vacuum/heat operated flap in the air filter nozzle. One second-hand filter housing later, problem solved. If only I had sussed it out that simply in the first instance...
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wrong carb diameter leading to chill factor
connect the intake to the manifold heater or change the carb to a twin
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I'm not familiar with the Golf engine layout, but are the carbs situated directly above the exhaust manifold? If so, it might be the carbs aren't icing but overheating.
I had exactly this problem on my road-rally Avenger many years ago. Everyone told me it was icing, but it turned out that the twin 40s were overheating with the heat from the 4-2-1 manifold directly below. Two pieces of ally plate (from the Uni workshops) and some loft insulation (from the digs) sorted it out.
Just a thought.
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Thanks guys for all the advice. Turns out it was the heat control flap in the air box, just so happened that i had a spare and now she drives like a dream, kind of. So thanks again and no doubt il be posting again soon.
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Thanks for the update, and glad it's sorted.
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