Car not starting / misfiring / gremlins

[werdna]

Hi all,
Thought id' post this up before I get back to the car to check it out.

Receieved a call from my girlfriend saying that the car died on her and was running very badly. She also said there was a small amount of smoke out of the bonnet. The car in question is a 1750 gtv.

After pulling over she opened the bonnet and said everything looked fine. - no actual fire or anything.

I have noticed the past few times I drove it that it was little rough on acceleration and at times had a funky idle (both symptoms only when hot). Other than that no real issues.

The car has a crane cams and bosch gt40 ignition setup.

I have a feeling it could be a dodgy ignition coil, or potentially a bad ballast resistor. That would explain the smoke, bad running when hot. Half tempted to pick up a replacement coil on the way to check out the car.

Anyone have any suggestions or think im even on the right track?

Thanks,

Andrew

[werdna]

Update:

I've had a look at the car and brought it home.
Started easily when cold, doesn't run well - like its out of time or on 3 cylinders. Idle is super low and lumpy - 600 rpm from what i can tell - who knows with the mechanical gauges though.
After testing and swapping out parts, and the car was warmer the running became worse at idle with spluttering through the lower revs. Sometimes seeming to even out and run fine from 3/4k
New distributor cap - no change
Swapped in the ballast resistor from the super - no change
Changed my leads - no change
As always - my intuition is incorrect.
All the cylinders seem to been running - all exhaust manifolds seem to be of an even and hot temperature.
I'm now leaning towards the issue being vacuum related.
After dinner i'll look at blocking off the brake booster hose, trying the motor without the oil cap and checking the breather hoses etc.
Also, what are the symptoms of a screwed ignition coil? is this something I should look at?

The joys of a 45 yr old daily driver....
Andrew

[colcol]

Pull out the spark plugs and seeif they are all the same, ie wet, dry or oily?, then if you are happy that are ok, put them back and run the car and pull the boots off the spark plug leads and short out each lead against the cylinder head with a big insulated screwdriver, then you will be able to see if you have spark, if you have a good spark on each lead, short out the leads again and listen for engine note, if it drops down the idle and runs rougher, then that cylinder is ok, if it makes no difference, then that cylinder has a fault, ie blocked carby jet or spark plug faulty, etc.
The ballast resister should have 12 volts from the ignition side and about 7 volts going to the coil, so that it runs on about 7 volts normally, the coil should get about 9 volts from the starter motor when cranking, so that the coil produces a good fat spark for starting, but this would burn out coil if running like this all the time, so when the engine fires it drops back to 7 volts, check it out with a multimeter / voltmeter, Colin.

[LaStregaNera]

If the car is fitted with a crane ignition module, it should NOT have a ballast resistor.
I'd be checking the connection to the vacuum booster (rear cylinder), the vac spigot on the front cylinder's intake (usually connected to the valve cover breather - some connect it to vac advance dizzies if they fit one),  and the condition of the carb mounting rubbers.
Might also be worth pulling the tops off the webers and cleaning out the jets - When I first got my car it had similar symptoms, which came down to corrosion/grot blocking one of the jets (It had been sitting for 10 years).