Volkswagen Golf II 1.3 1988 F reg - my car wont idle when warm. help please? - raver1234

when i first start my car it runs fine without any problems, and i can drive it around for a while untill the choke knocks off then i have problems...

if the cars already warm when approaching/sitting idle at a junction or lights etc it struggles to tick over and frequently cuts out, the engine starts to judder and struggle.

any ideas please??

Edited by raver1234 on 13/01/2011 at 22:13

Volkswagen Golf II 1.3 1988 F reg - my car wont idle when warm. help please? - raver1234

oh and i forgot to mention that its perfectly fine at high speeds and dosent lose power whilst crusing. but does as soon as i take my foot off the revs when coming to a stop.

Volkswagen Golf II 1.3 1988 F reg - my car wont idle when warm. help please? - Steven Quas

From memory a 1988 1.3 Golf has a carburetor rather than injectors? I assume it has an automatic choke. If both of those things are correct then you may just need to adjust the idle speed on the carb. The reason that the problem only appears when the engine is warm is that the choke is masking the problem by raising the idle speed when cold.

Steven Quas , Hamburg

Volkswagen Golf II 1.3 1988 F reg - my car wont idle when warm. help please? - unthrottled
Ah! Not too many carby cars left on the road these days. You'll need to find an 'old man' to fix this, a lot of garages will be scratching their heads because they can't find the diagnostics port...;)

Most problems attributed to carbs are not actually due to the carb at all-resist the temptation to 'tweak' the mixture screw. Unless you have a CO probe, you're just guessing, and you can do a lot of damage if you get the mixture wrong (too rich can be as dangerous as too lean). You don't know how your new mixture will behave under load (which you CANNOT simulate by blipping the throttle).

This is a one instance where 'reading the plugs' is likely to yield dividends. Run the car on your drive until it warms up and stalls. Leave it to cool down. Do not restart the engine or the results will be invalid. Remove the plugs and look at the colour of the tips. If the tip is black and sooty, the mixture AT THE LAST FIRING EVENT was too rich. The block capitals are intentional. The engine must be switched off/stall under the conditions of interest, otherwise the effect will be masked.

If the mixture is too rich, I suspect that the carb float bowl is stuck open, flooding the intake manifold with fuel, which under low air flow conditions causes a very rich mixture.

Conversely, if the spark plug tips are grey/white, the mixture is too lean. Given the age of the car it is highly likely that a vacuum hose has started to perish and is admitting air. Check any hoses that are connected directly or indirectly to the intake manifold. A good 'leak test' trick is to spray a gaseous fuel-(I use a bottle of propane cigarette lighter refill) around the vacuum hoses. If the revs momentarily pick up, you know that: a.)you have a vacuum leak and b.) that the manifold mixture was too lean.
If the revs momentarily stumble you know that: a.) you have a vacuum leak
b.)the manifold mixture was too rich. (unlikely!)

Good luck!