So I have a weird problem on my golf 1.9 TDI 2007, when I switch the ignition on the car starts up however as soon as I let go of the key SOMETIMES the engine will shut off. Sometimes the car will stay running no problem. When the engine shuts off i have to switch ignition to on to start car, hold the key in on position and very slightly give gas for a few seconds. Then when I let go of the key, whilst still having gas pressed, car will stay running. At this point when letting the key go rarely it tries to shut off for half a second the engine will shut off/skip but then stay running. Some background, this problem only started happening when 2 weeks ago I switched the ignition on and the engine was shaking a bit so i gave it some gas but gave too much and the engine shook a lot then shut of. When trying to switch back on it wouldnt start, it would crank but no start. I left it till the next day and it did start after some cranking but then this problem started. It starts first stime straight away now. Also around 3 weeks ago i changed the ignition housing and switch, could it be to do with the electrics in the control module under the steering wheel? No engine light, no fault codes. Very perplexed.