I have a grand c-max with a 1.6 diesel engine. It's one year old and has had the problem described below since new. My wife drove it for the first few months and I initialy thought she was having problems adjusting to a new car...
The problem is that the throttle doesn't seem to respond correctly - this is more noticable in lower gears when changes in engine power is most noticable. If you are travelling along at a steady speed and want to increase speed slightly (say, to keep up with traffic) and just increase the throttle setting a little as you normally would, initially there is little repsonse from the engine, perhaps for a quarter of a second. Then the engine seems to increase power excessively and the driver has to back off the thottle, resulting in an unpleasant ride. There is no lack of power as such, once the throttle does respond.
I've seen this problem (although described differently) in several places on the web, but noone has posted a solution. Most people report it as a problem in first gear, but it's just less noticable in higher gears.
We've send it back to the dealer to have it looked at several times and, as is usual with Ford, they 'couldn't find a fault'. The last time we went out with a technician and he said there was nothing wrong - he was driving, had a heavy right foot anyway, and made it clear from the beginning that if there was no upgrade/fix from Ford they weren't interested. Basically the dealers attitude is that if the car doesn't report a fault itself (via its inbuilt software) then there is no fault. I guess that means that if there is an actual design fault which gives no error it's never acknowledged - this is an appalling attitude.
I have a couple of questions regarding this, and any help would be appreciated. Is this a known fault? Has anyone else had this problem, and if so is there a fix? I assume this is a programming fault with the engine, so if we accept the issue for the time being will an aftermarket upgrade help once the warranty has run out?
Thanks in advance...