105JTD Bravo running away.

[Dave Ainscow.]

Idle speed set at 850 rpm. When approaching hazard in 4th.- change to 3rd. and engine slows down to less than 10mph and 500 rpm - then takes off up to 20 mph and 1200 rpm on it's own - feet off everything. I have a Peugeot Diesel which doesn't do this. Have had diesel control unit checked and Maindealers say is OK { still in warranty }
Anyone got any ideas on what to check next please ?.

Dave 'A'.

 

[kavman]

revs

This is just an idea: the idle speed for the JTD is 850RPM give or take and forcing the car down to 10mph in 3rd at 500rpm is basically asking the engine to return to its standard 850rpm. This particular engine is VERY torquey, and left to its own devices at 500rpm in 3rd would most likely simply accelerate back up to and slightly beyond the set idle speed. Does it eventually settle back to 850? If this is the case, then either develop a nice coasting style of driving or else use the other two lower gear ratios and see what happens. I have pulled a Hiace van out of mud, in reverse, at tickover, with my own JTD.

 

[Michael]

JTD "Cruise Control"

It's a case of "they all do that"-my Marea 130 is just the same-for once a dealer isn't talking complete cobblers just to get rid of you!Apparently the Peugeot/Citroen 2.2 HDi's are the same too.A feature of the engine management set-up it seems.

Michael

 

[David]

Peugeot know all about diesels....

So much that they purchased the right to use the Fiat common rail diesel design......... as did Ford, Mercedes, Shitroen to name but a few.