607 HDi runs rough when cold

[jimboy124]

Hi .... I have an 2005 607 HDi 2.0 ..80k miles ..

When the engine is cold it will not rev past 3000rpm ..And creates quite a lot of white smoke. When i first start the car when cold and go to maximum revs (which I know is not a good idea!) it will hold but then missfire and drop to 3000rpm .. When the engine gets to normal running temperature it runs fine with no hesitation at all ..

I have also used a can of EGR cleaner directly in to the air intake manifold ...

I have also changed the fuel filter,air filter,DMF and cam position sensor. .... I have had the pump checked for vacuum leaks and all pressures are fine.

totally lost on what to do next !

Any ideas ?

Regards Jim

[Hell Razor5543]

How cold is cold? While the HDi engine is very good at starting in cold weather I wonder if one (or more) of the glow plugs has failed? During the summer I never see the glow plug light come on when I am starting my C5, but in cold weather (zero degrees or lower) I do see it come on (how long depends on how cold it really is). If one glow plug does not work (all of the others do their job properly) it may be that that cylinder doesn't fire properly until it gets warmed up.

[myglaren]

Could be a failed plug as James suggests ^ or possibly the post-heating has failed.
On the HDi engines the glow plugs operate after starting even when not required o start the engine. This is to help with warm up and reduce emissions.

My first item to investigate would be the glow plug relay - don't as me where this is on a C5 as I have never had a problem with that part of the system, only on a 306 some years ago.

[white exec]

Test the output of the GP relay with a test-lamp or meter, to see when it is powering the GPs.
Main input to the GP relay is Batt+, output is direct to the GPs.
It switches the heavy electrical load of the for GPs (up to c.60amp total), and the relay's internal or external contacts may have become overheated or corroded.

[jimboy124]

How cold is cold? While the HDi engine is very good at starting in cold weather I wonder if one (or more) of the glow plugs has failed? During the summer I never see the glow plug light come on when I am starting my C5, but in cold weather (zero degrees or lower) I do see it come on (how long depends on how cold it really is). If one glow plug does not work (all of the others do their job properly) it may be that that cylinder doesn't fire properly until it gets warmed up.

Around 8 degrees c and below I reckon ... If i disconnect the MAF the engine will not misfire but it will rev past 3000 rpm ...

[GiveMeABreak]

If you have access to Peugeot Planet 2000 / Diagbox , any glow plug supply relay fault will show up as a fault.

Pop up your VIN and I'll locate the relay on the 607 engine.