My 147 2.0TS has an intermittent
problem that is isolated to cold starts. The problem initially occurred back in April whereby SOMETIMES when the engine is cold, I'd go to start it and at the point of kicking-over, the whole process seems very "weak" and juttery/rough. The revs would drop quite low (sounds as if it is about to stall) and it would struggle to reach idle speed. When it did reach idle speed, that itself was unsettled as well, ranging from 900-1200rpm. HOWEVER, the engine idles and starts perfectly fine when the engine is warm (or even if started a second time when cold) and the car drives as per normal. Furthermore, even when the problem occurs, the engine ALWAYS starts first time (even though it sounds as if it's about to stall).
The first time I took it in to the dealer (May), they witnessed the abnormal cold start themselves and diagnosed the injectors as in need of cleaning/service. This was performed and the problem never reoccured for 5 months, when it suddenly came back.
The second time I took it in (October), there was difficulty in trying to figure out what was wrong, but they diagnosed the throttle body in need of cleaning/service (no charge). This was performed and the problem didn't reoccur for a week, until after this when it gradually
exacerbated to the state it was before.
The third time I took it in (where it stayed for a week), they still couldn't figure out what was wrong, so they reprogrammed the vehicle electrics with the current software. They claimed to not find any fault during cold starts - this is crazy, surely in all this time it must have occured at least once!!! And sure enough, the day after I got it back, go to start and.....
IT'S DRIVING ME MAD.
I'm going to video the difference between it starting and idling normally versus playing up to show to them, but for the interim would really appreciate any ideas!!