Anyway, I've got a 2004 1.4 carb citi MK1 and have been getting this intermittent problem for the past year. This intermittent problem now seems to be getting a regular problem and I'm fed up.
Sometimes when i turn the key the car won't start, the starter is just completely and utterly dead. It also seems to happen more when the car is hot after driving to the shops or something, when it stands for a while and cools down i don't get it as much. Also the one moment it wont start then suddenly it starts no problem.
The only way i can start the car when this happens is by bridging the solenoid, then she starts up perfectly. When i turn the key all the instrument lights come on then go off as is normal and i can hear an assortment of sounds going on and off behind the dashboard somewhere as i turn the key on and off, but no start.
I have a new battery installed, i installed a new solenoid and have tested with a new ignition switch but no joy. I have read somewhere that the TP100 ignition module can also cause similar issues and that it is located in the rain gutter but mine's not there? where can it be? The guy from goldwagen swore that it was there when i asked but when he looked and it wasn't he was stumped and said its behind the dash somewhere. Should i look at fuses or starter relays or earthing to the body? i don't really know where to start.
Any and all advice for this noob who knows just enough "om kak aan te jaag" will be greatly appreciated!
Have a lekker one!
anyway he said its a voltage drop of some kind and he proceeded to fit a "booster relay" to the ignition wiring. she starts fine now after testing a million times on my way home 
so hopefully it stays that way.