Weird ignition behaviour

Just after some help with my DX engined Scirocco Mk2 which is giving me some serious problems.

The main symptoms are:

- Difficult to start - kicks back most of the time, and will occasionally reluctantly start and idle
- When idling, it misfires on all four cylinders, but does respond to the accelerator - if the pedal's pressed too hard though, it bogs down and dies
- When the ignition is turned on, but the engine is not started (position 2 on the key?), I can hear the lift pump and main pump prime, and simultaneously hear a 'tick-tick-tick' noise from the engine bay that carries on until the pumps stop priming. Having followed this, it turns out that if the coil-to-distributor lead is disconnected from the distributor and held near the block, the coil is sending a spark down the HT lead when the ignition is turned on. It stops when the pumps stop priming.

I can only think that this is an ignition fault, based on the last symptom - note that very occasionally, it starts and runs normally, and on these occasions, I don't hear either pump prime when the ignition is turned on, and there's no ticking (the fuel pumps priming is a new thing - it never used to be audible).

Any ideas? Really hurting for help here!

Is this a car that you have had for a while that has developed these issues or is this a new purchase that you are struggling to diagnose an issue with?

Sorry for not being clearer - I've owned the car for two years, and this fault has developed rather suddenly.

sounds to me like there is an issue with the dizzy/coil/TCI unit, seems its somehow sending a spark signal somehow to the relay hence the priming and ticking of the king lead. when it starts ticking unplug the hall sender, then try the tci unit, see if that stops it

Would the hall sender on the dizzy tell the coil to send a spark then? Didn't realise it functioned that way, but it makes sense.

Excuse my ignorance, but what is a TCI unit? Is that the same as an ignition amplifier?

I tried the following tonight:

- Disconnected the hall sensor on the dizzy - no change, spark still ticks.
- Disconnected the ignition amplifier - suddenly the fuel pumps aren't priming (which is seemingly normal for my car, since it never did it in the past), and the spark has stopped.

Now I know that the amplifier needs to be connected in order to provide a spark to the coil, but the fuel pumps sounding normal seems to be a fairly hefty pointer towards the amplifier being faulty. Anyone concur? Or is this a red herring?

just quickly check you havent got a hole in your fuel filler neck, friends car had same running faults (but not noticed elec faults) worked out it only ran badly after car had been in rain and water had got in the fuel.

yeah sorry TCI = ign amp.
i would get another one as your test does seem to point to it being bust. MK2 Golf ones work

it could be a wiring issue also, worth having a good look at it. there is bugger all to the ign wiring so its dead simple to check over, 3 wires from tci to dizzy, 2 wires to coil and an earth to the battery, simples.

I remembered this morning that I have a spare amplifier that came with the car, and it was reported as working… Hopefully it still is! I'll fit it tonight and give it a go.

Good to know the ignition system is simple enough - I did have a look at the book of lies last night and I think the amplifier is a good candidate. Failing that I do have the option of sourcing a dizzy and a coil for cheap moneys.

racer - One of the first things I did actually! Oddly my filler neck is still pretty solid despite it still being the original - one job this summer is to disconnect it and give it a damn good clean and about eighteen coats of hammerite to keep it that way! If this problem persists after the ignition system's been checked, I'll go into the tank and check for crap in the filter I think.

Gah, wouldn't you know it - the one spare part I need, I cannot find in my various boxes of bits. Fix delayed…

I would check all your earths before you do anything electrical,  :wink:

I checked the main earth strap yesterday - it's secure both ends. The coil-to-rocker cover strap is broken, but it's been like that since I bought the car, so it's unlikely that it's causing this; I will be fitting a new one asap though.

rocker strap doesn't effect the running of the car, but it can effect the dash. well, it shouldnt anyway. if it does, that would suggest a problem elsewhere

Quick update on this - got a new ignition amplifier fitted this morning and it's all sorted

Thanks for your help, everyone - who knew that such a small thing could result in such a big problem? Oh that's right - VW owners