Hey All,

 

New to the group just bought an 84 polo C 

Loving it however filled it up with E5 petrol today and it seems to be running rich to the point I can't put the choke in or the car judders and stalls (even when warm) any suggestions please, I was told about the idle screw however unsure where it is?

check the choke is working as it should , e5 shouldnt hurt it , its been on sale for a while now 

What's the best way to check the choke is working properly? When I collected the car the it seemed fine. After filling up I noticed the problem?

air filter off ...theres a butterfly /flap thats the choke, with a cold engine it would be closed or almost closed , as it warms up it should open fully

is this a new to you car>   do you know if its auto choke or manual?

The choke is manual, I know the car well as a friend has owned it previously

Choke flap closed makes carb richer, so its likely a lean condition, which could be an air leak. Carb rubber base mount is common fail point or any of the vacuum tubes to carb might be split.

 

Had it stood for a long time? Is the fuel filter clean?

So the car was restored (I don't know to what level mechanically) over a year ago and the car has been sat sorn for a year in a garage 

first thing see if that choke flap is working when you operate the cable , standing for a year wont have helped it 

 

does it have a clear fuel filter near the carb area?  is that clean , theyre only 50p or so 

Ok will have a look today, it has a brand new air filter in it and looks clean 

 

So checked the butterfly and choke. When I close the choke the butterfly is opening. When fully closed butterfly is open and then the car stalls and turns off. Also noticed a small whisper of smoke? 

 

I think your words of open and close are a bit muddled.

 

So the choke cable can move the butterfly to cut off (strangle or choke) the flow of air into the carburettor. This is choke on, passage closed.

 

With a properly working engine you should be able to gradually move the flap from fully blocking the passage to partially blocking and then in line with the passage as the engine warms to full operating temp. Unblock fully too soon and stall is likely.

Drive in lower gear at 2500 to 3000 to warm engine more quickly.

 

If you need to close the flap to keep the engine running, then either

not enough fuel or too much air is entering. (assuming plugs leads distributor engine earth straps in good condition and ignition timing is correct).

 

Not enough fuel could be restriction in fuel line or fuel pump.

Adding fuel to the tank might have disturbed rusty crud now in the feed line, but stopped at the fuel filter. Or if not stopped there have blocked the carburettor idle circuit.

 

Dry stored it is unlikely there is water in the fuel.

 

Too much air could be a vacuum leak. If you can get it to idle with choke flap as far open as you can, then spraying carb cleaner around outside of carb (not the intake) will make engine slow if any sucked in through a leak. Using easy start spray (diethyl ether) will make engine speed up. Listen for the noise change.

 

Which engine - 1.0 or 1.3?

They have different carbs.

And different idle mixture screw and idle speed screw locations.

If the whisper of smoke came out of carb when engine stalled and hot engine it is probably okay. Just burnt fuel not being pushed down the exhaust.

 

Is it easy to start? If not dirty crud could have reached the needle valve, so the carb is flooding with fuel (as not sealing completely when the float rises) and excess is dripping into inlet manifold. Running with choke flap across the passage then sucks more fuel and hides signs of the leaky needle valve.

 

Only when starting and first mile or so after cold start should the choke knob need to be out  and flap blocking or partially impeding air flow.

Edited 4 October, 20214 yr by dvderlm