Over the past 6-8 months my 2011 (<40k miles on the clock) Ford Focus 1.6 Zetec has started to stall. A lot.
It's worse in busy traffic with a lot of stopping and starting or at a slow speeds such as approaching traffic lights, however in recent months it's started happening on dual carriage ways and motorways at 60-70mph. It can go for a week without stalling once, or some days it will stall 10-15 times in a single 30 minute journey.
The revs idle at around 750rpm, which will then judder between 1,500 and 400-500rpm, at which point it will either recover itself and return to normal, or more often stall. There are no fault codes, no lights or warnings on the dashboard and it's since passed an MOT.
- The battery has been replaced
- I've cleaned the MAF sensor
- We ran a test on the idle sensor, which apparently is fine (though I'm no expert)
- I've had it plugged in at an engine mapping specialist and they couldn't find any errors on the sensors
I've read a similar post (2000 Ford Focus, low idle, stalling at lights, white smoke from exhaust - P0171 Code - problem?) but it seems that vehicle has other issues and is 11 years older.
If anyone has any ideas I'd be really grateful!
UPDATE 2018 - The car was returned to a Ford dealer for its service and MOT, the fault was demonstrated to a Ford mechanic but after extensive diagnostics, an issue could not be found. Due to consistent stalling while entering roundabouts and on the motorway, the car was scrapped.