Stalling and Engine Malfunction Service Now, Fiesta S1600

[SwanseaS1600]

Hi,

for quite a few months I have had periods of lumpy idling on my 60 plate S1600, sometimes when coming to a stop in traffic the revs will drop and it will stall. My local Ford dealer ran diagnostics and found nothing, so I have had to live with it.

In the last 3 weeks I have started getting "Engine Malfunction Service Now" and limp mode. Ford had the car last week for diagnostics and nothing found. A few days later the error happened after work so went straight there and they got a code indicating a failure on the throttle pedal. What they did to test was that they installed a replacement from one of their demonstrators to see if that helped. The frequency of the failure dropped from 3 times a day to twice in 4 days.

The car is booked in for a new throttle pedal tomorrow, however this morning the engine malfunction happened again, but this time I had an ODB2 reader - the code is "P2135 Throttle/Pedal Position Sensor/Switch A/B Voltage Correlation". I'm wondering if the pedal is actually at fault since they claimed to have put a spare on already or if there is something else wrong.

Can anyone offer any advice?

Thanks