406oc.co.uk

my 110 hdi is lump when cold , it's not like when a glow pug is knackered, it starts first time and sound ok but for about the first 5 miles or so when i pull up at a set of lights or a junction i can feel that it's not idling right ,feels a bit lumpy as though it missing.
once the temp guage is up to about 70c the car feel fine.
checked car with PP2000 and the only error code i get is "coolant temperature inncorrect value received" do you think this is maybe the problem maybe new sensor needed ?

davew wrote:my 110 hdi is lump when cold , it's not like when a glow pug is knackered, it starts first time and sound ok but for about the first 5 miles or so when i pull up at a set of lights or a junction i can feel that it's not idling right ,feels a bit lumpy as though it missing.
once the temp guage is up to about 70c the car feel fine.
checked car with PP2000 and the only error code i get is "coolant temperature inncorrect value received" do you think this is maybe the problem maybe new sensor needed ?

Anybody any more thoughts on this,
Mine started to display these symptoms about 6 months ago & is getting slowly & progressively worse,
I will admit that I haven't checked it out at all yet due to the crap weather & time of year.
But a quick reminder, my car is a two owner, F.S.H with 103 thou now showing, I do oil & filters (oil & fuel) every 6k,
I only run v power & millers eco boost diesel treatment .
+ when I do the fuel filter I use forte diesel treatment to 30 litres of fuel & give it an Italian tune up
The egr/dosser has been blanked/removed as has the cat.
The symptoms are when trying to hold a steady throttle between 1000 & 2000 rpm's some times (mostly when warming up )
It can miss/stumble/jerk, it didn't use to do this, it will also miss while ticking over at the lights or a junction
Any ideas would be greatly appreciated.

Unless its an electronic fault or low compression on one cylinder I would suspect an injector, providing everything is working as it should the injectors have the final say as to how much fuel goes in and how well atomised it is. You can do a leak off test to the injectors by extending the leak off pipes into four similar sized containers and checking the flow from each, if one passes a lot more its leaky internally which will affect its performance.

Injectors are pretty reliable in the 8 valve engine, as far as I know the silver one has the originals at 245k but I know I have a problem with the C5 and my new 406 is only managing about 40 mpg where the old one does 60 mpg so I'm hoping that's an injector problem to.

The good news is that I bought a set of four from ebay for £25.

Peter

I had this issue

viewtopic.php?f=5&t=23864

Bucking/rocking/missing when cold, plugged in PP2k and looked at injector correction values. Turned out injector number 3 was not delivering enough fuel and had lots of leak off, replacing the injector cured the issue.

Thanks for the replys guys,
I was thinking leaking injectors / fuel pump in tank issues but the weather has been bad of late so no chance to look into yet
First dry Saturday & I'll be on it