Poor start-up
QMy problem concerns a 2007 Renault Modus 1.4 petrol with 63,000. The Renault runs great, except for one small problem, on start-up it idles to about 1200rpm – and revs correctly – but after only a few seconds drops to 700rpm then stalls and pops.
After a few minutes it then revs normally. There are no lights on dashboard. I have tried a new air temp sensor, and intake manifold pressure sensor, to no avail.
Any help greatly appreciated.
Jack Palmer
AThere are a couple of common issues which Autodata has alerted me to on your vehicle. The first is the possibility of ignition coil problems and although I would normally expect this to give a wider range of problems than you have, it would be worth checking them to be sure. The faulty coils were up to production number 330-03 and the production number can be found below the electrical connector on the side of the coil.
The second common issue which may well have a bearing on your problem is the possibility of a faulty crankshaft sensor. This does give the symptoms you have and would be worth replacing. It is quite possible for the crankshaft sensor to begin to fail in this way, but not cause any engine management codes to be flagged at this stage. Its continued decline could though cause further issues if this is the problem.
Finally, another cause of the problem may be in the throttle body and may be a faulty position sensor, and if replacing the crankshaft sensor gives no improvement, then cleaning the throttle body would be the next step.