Rover V8 3.9 EFI fast idle when hot issue

SimonAspin · Post by **SimonAspin** » Wed Apr 04, 2012 11:23 am

Hello All,

wonder if you can help, I have a 3.9 Rover from a 97 Dicovery in my Defender. All works well except for when the engine gets hot the idle speeds up quite significantly.

If I start it from cold and just let it sit as soon as it hits normal operating temp it speeds up. When driving and using it, it will sometimes run fast at idle other times it will be ok.

It runs fine in every other way and the emissions seem fine as they were average at the last mot.

I have replaced the stepper motor and nothing changed. Please help, alternatively if there is someone Near Rushden NN10 who specialises in the EFI set up please can you let me know and I will see if I can get it booked with them.

Thanks
Simon

Ian Anderson · Post by **Ian Anderson** » Wed Apr 04, 2012 12:36 pm

Enough return spring on the throttle connection?

IAn

SimonAspin · Post by **SimonAspin** » Wed Apr 04, 2012 12:53 pm

Ian Anderson wrote:Enough return spring on the throttle connection?

IAn

Hello Ian, thank you for your reply, yes this is all fine, it closes up real quick when the throttle is released and I keep it well oiled/greased and clean.

I am pretty certain it is a electrical/ECU issue as quite literally as soon as it gets to operating temp it speeds up.

Thanks
Simon