S40 (New) Engine 2.0D : Smokey Start (grey smoke), lumpy/jerky until warm. HELP!

[kylemoon]

Hi all,

I'm really hoping someone here can help with my 2008 S40 2.0d.

When the car is left overnight, usually 12+ hours, next start is very lumpy and smokey. Grey smoke, smells like unburnt diesel, for around 30 seconds. Smoke will stop but lumpy idle will remain for a few minutes.

Partial throttle (5%-10%) will result in a lot of jerkiness, this will stop if you apply more throttle, or until it's warmed up.

Garage found a leak on the injector leak back pipes, so all replaced. Still the same. I'm convinced it's injectors rather than glow plugs as it always starts on first or second crank even if cold outside. They've quoted £150 just to look at the glow plugs.

Car is fine when warmed up, pulls well, no lumpiness, although quite loud 'diesel knock'.

Anyone have any thoughts? Would be so so so grateful. Thank you!

[138gat]

If it's showing a code for glow plugs, ignore it as probably a ghost code.
It has to be freezing penguins before these use glow plugs to start.
Had a similar issue with mine but loads of smoke and knocking/clanging on acceleration, got better when hot
Leak off test done by my local indie found a injector to be at fault.
Replaced said injector with a second hand one out of a mondeo, no re-coding , never had a problem with it since and that was about 4 years ago
Hope this helps

[kylemoon]

Originally Posted by 138gat

If it's showing a code for glow plugs, ignore it as probably a ghost code.
It has to be freezing penguins before these use glow plugs to start.
Had a similar issue with mine but loads of smoke and knocking/clanging on acceleration, got better when hot
Leak off test done by my local indie found a injector to be at fault.
Replaced said injector with a second hand one out of a mondeo, no re-coding , never had a problem with it since and that was about 4 years ago
Hope this helps

Thanks for this, yeah -2 I've read is when the glow plugs are used. It's around 7 degrees where I am.

I had a leak off test done and all 4 injectors passed, but it does sound like one is leaking down over night..

Was it difficult to replace the injector? Is it just a case of getting the right class? I'm going to take them off soon to have a look, but worried about air getting in, and whether I need to invest in a torque wrench to put them back on.

Thanks for your reply btw!