High idle until brake pedal pressed 2.0 hdi

[Jodypug]

Hello,

I have a 2015 Peugeot Expert 2.0 hdi that has started to idle at about 1250 rpm, but if I press the brake pedal, the revs drop back to normal. Also if I switch the engine off for a minute or 2 it seems to reset itself. Sometimes I can drive for about half an hour before it starts doing it again or sometimes it will only go for 10 minutes before it starts doing it again. Also I think I have noticed that it doesn't do it whilst the regen is in operation.

I have been to my usual independant garage and they don't know what is going on, they changed the brake light switch thinking it could be that but it didn't make a difference.

I have spoken to another garage and they have never heard of it and also an auto electrician that has never heard of it either.
The garage seems to think it can't be a vacuum leak as the brakes operate exactly as they should.

There is also nothing flagging up on the diagnosis apart from a turbo vanes problem that has been showing for a couple of months.

I have done a Google search and found a couple of other people that have had the same problem and even someone in this forum, but they haven't followed up with any updates if they found a fix or not.

Please help, it is awful to drive and sometimes a little dangerous due to it trying to drag me along if I let the revs drop too low.

TIA

[RichardW]

It's probably an issue with the accelerator pedal - the 1200 rpm and rev drop on brake press is the default strategy if the pedal is not present. I'm surprised it hasn't flagged a fault for it however. You could look in live data and see that the two tracks from the pedal are doing the same thing.

[Jodypug]

Thank you, I will have a look into this. And yes it's so fustrating when nothing flags up on the diagnostics