Hey everyone, wanted to bring this topic back as I might take action on this soon. 

Since I bought the car 8 months ago whenever I start it when it's been left for over around 2 hours it puffs white smoke for a few seconds along with being lumpy on idling. The lumpiness goes after about 1 - 2 minutes of driving. There is a strong smell of diesel from the white smoke. When I start the car again not long after it's had a good drive it starts perfectly. 

Me and my dad are thinking it's an injector which is leaking. Recently checked the oil and coolant levels and thankfully they don't look like they've gone down which is good. When we first noticed it we changed the glow plugs as faulty plugs can give similar symptoms however this hasn't cured the problem. There's a company which deals with these hdi engines and can recondition the injectors along with supplying the injector seals.  

Thought might get other peoples opinions if they'd agree or have other thoughts on another thing. It's a 1.6 hdi engine (diesel) 

5 hours ago, zain611 said:

whenever I start it when it's been left for over around 2 hours it puffs white smoke for a few seconds along with being lumpy on idling. The lumpiness goes after about 1 - 2 minutes of driving. There is a strong smell of diesel from the white smoke.

Forscan, and some other systems like Torque, I think, can monitor fuel rail pressure.

If there is appreciable residual pressure after turn off, and this then drops away over an hour or so, that would back up the leaking injector theory. My car holds appreciable pressure over many hours, though I did not record the numbers.

If the pressure stays constant, then it is unlikely to be leaking into the cylinders while standing.

If the pressure drops to near zero straight away, then the ECU is probably dumping the pressure using the relief valve (PRV) on engine shut-down. This also makes the leak less likely.

If it is taking more than about 4 compressions to start, then the fuel could be being injected during the starting attempt, but something else, maybe poor compression, is delaying it firing up.

to be honest if the problem does not actually affect your use of the car I would be tempted not to start messing about with the injectors in case you end up with worse problems afterwards. If it ain't broke.............

11 hours ago, Tdci-Peter said:

Forscan, and some other systems like Torque, I think, can monitor fuel rail pressure.

If there is appreciable residual pressure after turn off, and this then drops away over an hour or so, that would back up the leaking injector theory. My car holds appreciable pressure over many hours, though I did not record the numbers.

If the pressure stays constant, then it is unlikely to be leaking into the cylinders while standing.

If the pressure drops to near zero straight away, then the ECU is probably dumping the pressure using the relief valve (PRV) on engine shut-down. This also makes the leak less likely.

If it is taking more than about 4 compressions to start, then the fuel could be being injected during the starting attempt, but something else, maybe poor compression, is delaying it firing up.

Just reading all this makes me worried if there could be a worse problem lol. When it turns over it normally takes about 2-3 cranks to start it occasionally 4 so does that mean compression is good? This is when I start the car in the mornings. The amount of smoke that comes out isn't linked to the amount of time the car has been sitting. Once I left the car for about 2 hours after it's been driven for 10 miles and it puffed a bit of smoke for around 10 seconds. Can't remember if it was really cold then as it could of also took out steam. 

2 hours ago, isetta said:

to be honest if the problem does not actually affect your use of the car I would be tempted not to start messing about with the injectors in case you end up with worse problems afterwards. If it ain't broke.............

I remember you saying the same thing isetta back on my last topic about this. It's just that I don't want it to get worse if it is a leaking injector. I remember you saying about not touching the glow plugs. That took my dad 4 hours to do as we all know the risk of them snapping off. 

Also didn't your brother or brother in law have your mk6.5 fiesta with the 1.6 diesel and you said it would give the same symptoms as mine?

yes my brother has mk6.5 1.6tdci. I bought it in 2007 at 1k miles.  sold to my brother at 146k miles, it was doing the same thing then. I can't remember how long it had done it but probably at least 10k miles. It is now on 159k miles and just the same. It has not got worse and does not affect his use of the car. 

These don't have a MAF sensor, unlike the DV6 in most other cars, so rely on other temp sensors to determine fuelling for cold starts.  I would check the temp sensors are all reading correctly when cold if possible.

58 minutes ago, zain611 said:

it normally takes about 2-3 cranks to start it occasionally 4 so does that mean compression is good? This is when I start the car in the mornings. The amount of smoke that comes out isn't linked to the amount of time the car has been sitting.

2 to 4 compressions sounds good to me. Poor compression due to valve or ring problems will usually take a variable time to start, but often a lot longer than that. I had a leaky valve on an old petrol engine, that took a long time to start when it was warm, but was ok when hot or when fully cold, ie 5 munutes to an hour or so of standing.

Your car starts without smoke when hot. you said above, but smokes after standing for a certain time, so it could be the leaky injector idea, or just some part cooling down. The DPF or Cat, the exhaust, or just the pistons. And when cool, this generates or allows steam (from the burning fuel) through.

I am partly in agreement with Isetta about caution before removing injectors. Every time the high pressure piping is disturbed, there is a danger of dirt into the injectors. Even just wear debris from the pipe unions and seals. There are some very tiny metering holes in the injector, as well as delicate valve seats. Also pipes may not re-seal, in theory they are intended for single use only, as all the seals are metal to metal. Though everybody ignores this, at least up to the point where they leak. Curing leaks by over-tightening or by any sealant are very big No-Nos on this extreme high pressure piping.

So tests using diagnostic aids, including fuel rail pressure, VCV (Volume control valve) operation, and cylinder balance would be a safe first check. Then maybe an injector leak-off test, if they are still suspect.

Just seen Tom's reply, that is another good idea to check. Again, a diagnostic tool should show these readings.

Thanks everyone. Last I checked for error codes there was one i think said CANbus and the other was with the radio (no issue I could see however the button to lower the volume on the steering control is loose / sticky). The engine light came on months back and that was caused by the EGR however back then the car was just being driven in and out of the garage at low speeds for 2 months. Till now since that code got deleted I haven't had no light come on. 

Yeah it's just this risk when removing them. No one wants to try and sort out a problem and it then gets worse / prolonged. The seals were replaced at one point as there was remains of black dried goo on top of the cover which covers the injectors. I just get worried putting my foot down as I don't want it to put excessive wear on that faulty injector. 

The white smoke gives out a strong diesel smell just to remember so that must show that's unburnt diesel