1.8 GL auto mk2 H reg 137k miles, Occasionally carries on running for a few seconds when ignition turned off. Also possibly related is quite a few cranks needed when warm (starts almost instantly in the cold) and fuel economy is quite poor. Also it has occasionally cut out when coming to a stop and then difficult to restart and keep idling. It is the pierburg carb I presume as there is no manual choke, it doesn't idle at 1500rpm, engine seems to get up to temp ok. It will go up to halfway on the temp gauge when sat idling on the drive, but cools down considerably on the move. I know nothing about carb engines, and this car was destined for a 1.9D or 1.6D engine mated to the auto, but wondering if it is something simple?
Does it try and turn itself over again when you turn it off? Dieselling? Mine does that, always told not to worry too much about it really, just a bit of pre-ignition. Can't really comment on the rest, I'm running the same engine with fairly decent economy, you checked out the timing on it?
it just carries on running, sounds very rough when doing it though. Not checked the timing or even got any history for it. Economy I would guess at the low 20's, but the gauge moves around a lot compared to on my mk3 I won't be spending any money on it though, any cost on getting the timing belt done or carb set up could be spent getting the diesel in it.
was writing my reply before that last one came in. I guess i'll check up on that, and it probably needs a service anyway
Not hard to do the timing yourself mate just a matter of aligining everything up.. Deffo worth checking
First grab the missus or some other assistant. Then, with engine running and fully warmed up , pop the bonnet and look at this bit: Drivers side of carb, low down. When engine is (fully warmed up and) running the plunger of the unit to the left of the little yellow arrow should be sticking out about 8-9mm, and the little screw to the left of the arrow should be touching the end of the plunger. Don't attempt to adjust the screw if it isn't. As your assistant turns off the ignition, the plunger should retract fully to the left, and the little screw and the angle bracket bit should follow it to close the primary throttle completely, starving the engine of air and stopping it. If the plunger doesn't retract fully at ignition off, you probably have a leaky/dropped-off vacuum hose somewhere round the back of the carb. If the plunger does retract fully to the left, but the screw doesn't follow it at all, your waxstat needs replacing. (35-ish from GSF) The little screw may not follow the plunger all the way, but should definitely move to the left as the plunger retracts. Edit: Just to emphasise; if you don't let the engine warm up to full operating temperature, the results of this check will not be diagnostically helpful, especially with regard to the screw/bracket following/not following the plunger as it retracts.
I have had 2 causes for this on my carby 1.6. 1st was due to car running too hot, as rad fan had packed in 2nd was due to excessive carbon buildup in the cylinders to fix 1, make sure your fan works on both speeds. to fix 2, spray half a tin of carb cleaner down the carb inlet while its hot and running. you should note a large sooty stain on your driveway once done, if so thats got rid of all that pesky carbon
Ha just been out in the car, cut out at the barrier into a multi-storey (only entrance to it), got it going, then on way home it idles at 2k! How do you guys run these as a daily? Do they just keep going wrong and you keep fixing them? Got the car nice and hot yesterday, fan did work but it seemed too hot standing by the engine bay, gauge read ok. Also used some carb cleaner, not that much though
once you find the issues its a mega reliable car. After I repaired the carb my old driver was by far the best car I have owned in terms of day to day reliability, nothing ever went wrong with it!
Thanks all for the help so far. My observations today are: Autochoke housing gets hot after about 10-15 minutes or so of idling, as in too hot to hold a finger on there. I expect this would warm a bit quicker if driven normally? I loosened the hose clamp off it from the manifold and there was a slow drip once warm. Presume it should drip all the time when running? RE: the plunger photo'd above, When running to begin with, there is a gap to the screw of around 6-7mm. This drops down to 2-3 mm when hot. The plunger doesn't appear to touch the screw while running When the ignition is turned off - the plunger extends about 6-7mm I think. The engine was trying to run on a bit at this point. The advice above mentions it should fully retract, but the FAQ says it extends to 14mm, retracting to 8 when started? The car starts well from cold, but it stinks of fuel. I put a load of carb cleaner (liquid not spray) down it yesterday. The stink seemed to gradually reduce as it got hot. The choke flap when hot is fully vertical - but I didn't check how long it took to get fully vertical, should I? Is it fair to assume it became fully vertical when the housing got too hot to touch?
The symptoms seem to follow this link off another thread. If it is this, and the autochoke housing getting hot is just radiant heat from the exhaust or something, then instead of taking the manifold off, can the coolant feed from the manifold be blanked off and a T put in to another coolant line and the autochoke be fed from that?
when you say loosened, was the hose still attached though? there should be a good strong flow of water out of the manifold at all times if you take the hose off while its running when the engine is switched off the plunger should retract for a bit, then re-extend fully. the fact it doesnt retract suggests a vac hose is missing, or the unit is faulty. this would explain the run on, as its forcing the throttle to open, rather than allowing it to shut like it should.
The hose was still attached, when it cools down I will take it off. I will re-check the vac hoses, I did replace a couple as they were a state. What do you think about the screw never touching the plunger? Is that few mm the difference between it idling at 14-1500 and 900rpm?
as above it sounds liek something else is holding the throttle open, perhaps the waxstat as above. check for good coolant flow out of the manifold hose, you only need to run the car for like 30seconds from cold, just long enough so you can see if water is flowing freely or not
Sounds like you may be lucky-ish and just need a new waxstat. (I might even have a spare...) If the choke housing is getting that hot in a reasonable timeframe, and the choke flap is going vertical, it suggests to me that the coolant flow is at least adequate. Take the waxstat off (being v. careful not to round off the screwheads; the screws will be tight and possibly a bit corroded where steel meets ali and maybe a bit of coolant leakage). Then see how far the pin stands proud of the flange mounting face (not the inner brass bit) when the thing is completely cold. You may not have to disconnect either coolant hose to do this check, though I think one of them is kinda in the way of one screwhead. If the proudness is less than 2mm, and it goes in further than that when pushed with modest force, the waxstat is kaput. I don't believe the urban myth that these things can be 'reset' in boiling water, once the wax has started to leak out, there's no getting it back in there.
The hose does have coolant flowing out of it, though it is brown so a coolant flush does seem imminent. Is the hot autochoke in 10-15 mins a reasonable timeframe, or should it be sooner? Sorry to keep going over the basics, likely problems are: the 3/4P unit is either faulty or vacuum problem causing the running on, and the waxstat is keeping the screw off the plunger and keeping the idle high?
if its just sat it may take a while longer to warm up, since it gets direct flow of coolant from the engine the carb will take just about the same amount of time to warm up as the engine does sounds liek you have 2 issues, 1st the autochoke isn't retracting for whatever reason when ignition switched off, and something is also holding the throttle open too much.
