Ford Focus 2.0 TDCi - Blue Smoke :(

[cwhaley]

Does anybody know potential causes of the following symptoms on a 2008 2.0TDCi Focus?

- Excessive cranking when starting (only when cold)
- Large amount of light blue smoke for around 20-30 seconds after starting
- Rough idle which clears after 2 minutes

So far I have had the below work carried out:

- New heater plugs
- New injectors
- Battery tested
- Full service including fuel filter

This work has killed my wallet and the problem still remains!

 

[Burnerman]

A couple of things spring to mind, and it could be an idea to get the services of a diesel injection specialist.
Have the compression checked on each cylinder
Ensure current is actually reaching the glowplugs (you could do that yourself and hopefully that's it)
Have the pressure checked at the high pressure pump that feeds the common rail
Check for any software upgrades that are applicable to this vehicle (there have been many, and Ford know all about it.
Has the car done a huge mileage?
John

 

[cwhaley]

The car is on 100k but has been serviced regularly all its life (half of that was at Ford) and this is something which attracted me to the car.

The glowplugs were identified as "completely dead" by one diesel specialist so I had these replaced (at another garage) and there was no change at all which surprised me. I always let them 'warm up' for 30 seconds before starting and I can hear what I presume is a relay clicking 2-3 seconds after turning the key. How can I test these?

As the car runs well when warm and for the rest of the day, it's got to be something like this rather than bent con rods or other serious problems.

 

[Burnerman]

I don't think your car has serious issues, its just a case of isolating things really.....if you have a 12v tester you can see if current is reaching the glowplugs which is a very good start.
You don't need to let the plugs warm before starting up, as soon as the glowplug light on the dash goes out, immediately try for a start up....if you wait for even a second or two they'll cool back down again.
If you have the old plugs, an electrical resistance of about 1 ohm is the norm, and I'd doubt if they had all failed!
John

 

[cwhaley]

Thanks for the advice on this. The glow plugs are way down the back of the engine somewhere and really difficult to reach (typical) so I might ask a garage to take a look purely because they have an inspection pit. The old plugs were binned so no way of testing electrical resistance unfortunately.

I'll try your advice too on starting after the light has gone out (which is always 1-2 seconds). I didn't think they were used all that much in current temperatures, but everybody has been telling me to let them warm.

After I had the new injectors (no change in symptoms) the garage then wanted to look at con rods, but surely engine running would be poor all the time if one or more were bent?

 

[Burnerman]

Always go for a start up immediately the dash glowplug light goes out.....the plugs literally glow red hot in a very short time and cool down just as quickly after. The plugs may or may not come on again when the engine is running, but you won't be able to tell when - apart from maybe a slight dimming in the headlamps, believe it or not!
Common rail direct injection engines don't employ the plugs for long - and some engines not at all unless the temperature is very cold indeed. Indirect injection diesels have the plugs heating for much longer, say 12 sec.
If all else fails here, and the glowplug system is guaranteed working, a compression test is advised, but I'd very much doubt if bent con rods were the cause! There's no reason to suspect this at all, but low compression does manifest itself in poor starting and smoke.
If the engine has a nice even beat when warm and the tickover speed is normal all should be ok here.
Be lucky!
John

 

[cwhaley]

Always go for a start up immediately the dash glowplug light goes out.....the plugs literally glow red hot in a very short time and cool down just as quickly after. The plugs may or may not come on again when the engine is running, but you won't be able to tell when - apart from maybe a slight dimming in the headlamps, believe it or not!
Common rail direct injection engines don't employ the plugs for long - and some engines not at all unless the temperature is very cold indeed. Indirect injection diesels have the plugs heating for much longer, say 12 sec.
If all else fails here, and the glowplug system is guaranteed working, a compression test is advised, but I'd very much doubt if bent con rods were the cause! There's no reason to suspect this at all, but low compression does manifest itself in poor starting and smoke.
If the engine has a nice even beat when warm and the tickover speed is normal all should be ok here.
Be lucky!
John

Thanks, John -- really appreciate your words. The garages I took my first cars to (10-15 years ago) were ran by men who had been doing it for decades and are all retired now. I went to them as my dad and his dad used them so there was a lot of trust. Now I have to go to places I've never been before and the philosophy seems to be "replace parts until fixed".

Sounds like the advice I've had on heating the glow plugs is a hangover from older generations of diesel engines. As said mine runs fine when warm, idles at a very constant 750rpm and is quite quiet. It's just this embarrassingly rough start on cold mornings.

Next steps are to check current flow to plugs and a compression test to see if there are broken seals. Will post updates on here.

 

[UncleB]

It would be worth checking for blue smoke from the exhaust when the engine is warm and the car has been idling for a minute of so then is driven hard - this would indicate the turbo shaft having excessive play and also causes the slow leak of oil when sat overnight which causes the oil burn initially.

It is not the most obvious choice but one that indicates potentially imminent turbo failure that can get very expensive due to knock on damage when it disintigrates so it worth having checked.

If these symptoms are present then a mechanic can take the cover off the turbo and check for movement in the shaft that will establish if it is the case - quick and easy to diagnose.

The downside it that you probably would need a replacement turbo...

Good luck.