Peugeot 406 2.0 HDI 90HP, cold start problem

[AndreiNCS]

Hi guyes,

First of all, sorry for my bad English, I'm not from UK.
I bought my Peugeot 406 in april 2013 from a cousin, so I know that the car had everything changed when needed ( oil, filter, coolant, etc). Starting from november 2013 , when the temperature droped below 15 degrees, car begun to start heavier ( I'm from Romania, where in January temeperature sometimes it's even -20 C degrees). The engine cranks fast, i don't thing it's a the starter or the battery. Because of "financial" issues, I went to different garagues. First I've changed the glow plugs relay. No improved. Then I've changed the glow plugs, fuel injection pump, coolant temp sensor....last week I've changed 3 injectors, no improvement. So, since then, the engine cranks fast enough, everithing it's on parameters, but the car starts only after 2-3 keys and it blows a lot of white / slighthly blue smoke. After getting the car started, it will start with no problems, as long as the engine it's hot. After 3-5 hours, depending of how cold it's outside, again the same problem. In the summer, the car starts perfectly. Here's a video form 17 Jan 2018, at 6-7 C degrees , after -2 on the night: https://www.youtube.com/watch?v=zr66op4 ... e=youtu.be

Once again, sorry for my bad English.
I'm waiting for your sugestions!

[steve_earwig]

Hi Andrei, welcome

Your English is fine, much too good to be Google .

Is the injection pump siemens or bosch? The Siemens system has no low pressure/lift pump in the fuel tank and what happens with these is if they have a slight leak in the line the fuel can drain and then they are hard to start. What they do have is a primer bulb under the bonnet which you can use to prime the system, which should make starting it much easier.

[AndreiNCS]

Hi, Steve! First thanks for your answer. Do you mean that black rubber bump from diesel filter to the injection pump?! If so, I tried, I've squeezed it until got harder, but without significant improvement when starting the engine. What I have noticed and forgot to mention, is that if unplug the coolant temp sensor jack from the engine, then then the glow plug sign from the dashboard is on for like 10 seconds, and the car starts way better, after that I immediatly reconect it, and still got the smoke and 1 minute of engine working weird (RPM have small deviations, between 700 to 1000 RPM, but after that, it will be constant at 800). Injection system is Siemens (diesel pump, and injectors).

[steve_earwig]

That is what I meant yes

HDi's shouldn't need to run the glowplugs for that long to start, and the white smoke is probably unburnt diesel - did you have any tests done on the injectors? It appears you've changed everything else...

[AndreiNCS]

Yes, last week I've been tested them, and 3 of them were fault, so I changed them with 3 new ones from second hand, but before putting them on the car I've testem them also and they're parameters. Video above it's after what I have changed them. So not injectors are causing this issue...

[Welly]

I'm wondering if the head gasket is leaking into one of the cylinders, could be worth getting a 'sniffer' test done to check for combustion products in the coolant water? that white smoke looks like steam to me

This problem would still be happening in summer but the engine is more willing to start quickly in warmer temps.

Do you need to add coolant regularly or are the coolant hoses rock-hard with the engine running?

[AndreiNCS]

Hi, Welly! I also was thinking at head gasket, but a compresion test was done twice, in different services and it's on parameters, no value to worry about... I loose some coolant, but that is happening at the thermostat housing, it's a little crack on that plastic housing.

[GingerMagic]

Hi, welcome.
My initial thoughts were injectors - I must admit I'm surprised you changed just 3, not the full set - I bad injector will certainly affect the starting in the morning
Maybe change the CTS, it's not too expensive and relatively easy to change - a faulty one will give all sorts of problems with over fuelling, under fuelling etc.
Also, try ignition on, ignition off, ignition on a couple of times to see if it is the glow plugs or relay.
Good luck.

[AndreiNCS]

Hi, welcome.
My initial thoughts were injectors - I must admit I'm surprised you changed just 3, not the full set - I bad injector will certainly affect the starting in the morning
Maybe change the CTS, it's not too expensive and relatively easy to change - a faulty one will give all sorts of problems with over fuelling, under fuelling etc.
Also, try ignition on, ignition off, ignition on a couple of times to see if it is the glow plugs or relay.
Good luck.

Hi, GingerMagic and thanks for your answer!

I was also surprised to see that only one injector works fine, but all 4 were tested separataley on special bench of probation, with detailed raport ... the trouble was at the back-flow, it had to be between 29-49 cmc/ minute and 3 of them where way above. I tried the ingnition on/off trick multiple times, but no effect... I verified if current reach to the glow plugs, if the relay works, and everything works properly.
What do you mean by CTS, i've google it and don't know what it means... as I mentioned in another comment, I'm from Romania, and my English is not that good, there are some parts that I don't know their names in English.

Once again, thank you for your answers and sugestions!

[Doggy]

Hi & welcome.

CTS = Coolant temperature sensor - the water temperature sensor in the thermostat housing.

From experience a faulty one can give odd starting and cold running behaviour, especially in cold weather.
To prove a point, get a new sensor, (only about £5 in the UK) and connect the cable to it without putting the sensor in the engine. If it runs properly you have found the problem and should fit it properly. If it makes no difference, no need to drain the coolant.

Good luck

[AndreiNCS]

Hi & welcome.

CTS = Coolant temperature sensor - the water temperature sensor in the thermostat housing.

From experience a faulty one can give odd starting and cold running behaviour, especially in cold weather.
To prove a point, get a new sensor, (only about £5 in the UK) and connect the cable to it without putting the sensor in the engine. If it runs properly you have found the problem and should fit it properly. If it makes no difference, no need to drain the coolant.

Good luck

Hi, Doggy

Thank you for your response!
I have tried 4 new sensors, every car-service has thought it's from that sensor, but no change, the car starts in same hard way.

Any other sugestions?
Thanks!

[frog]

Any other sugestions?

My 2 cents:

• Check the high-pressure fuel pump, especially:
  • the third piston deactivator (see "17" in figure "B1HP10VC" in chapter 6 of http://dispatchexpertscudo.org.uk/dw10fuelsupply.html), and
  • the pressure regulator (looks like this, or see "16" in figure "B1HP10VC" in chapter 6 of http://dispatchexpertscudo.org.uk/dw10fuelsupply.html).
• Check if the EGR valve is stuck open.

From own experience, and from http://www.aussiefrogs.com/forum/citro% ... ost1194186 :

I know of one high km C5 with a DW10B engine that turned out to have one of the three pistons a bit sticky and was very hard to start until that was addressed. Once running it was OK. The EGR was also a problem on that car and if they fail or stick open for some reason, then starting will be very difficult.

[GingerMagic]

For the record, the 3rd piston is in the fuel pump, it shuts off some fuel when not in demand.
It's the orange plug on the fuel pump.
Certainly worth a go

[AndreiNCS]

Any other sugestions?

My 2 cents:

• Check the high-pressure fuel pump, especially:
  • the third piston deactivator (see "17" in figure "B1HP10VC" in chapter 6 of http://dispatchexpertscudo.org.uk/dw10fuelsupply.html), and
  • the pressure regulator (looks like this, or see "16" in figure "B1HP10VC" in chapter 6 of http://dispatchexpertscudo.org.uk/dw10fuelsupply.html).
• Check if the EGR valve is stuck open.

From own experience, and from http://www.aussiefrogs.com/forum/citro% ... ost1194186 :

I know of one high km C5 with a DW10B engine that turned out to have one of the three pistons a bit sticky and was very hard to start until that was addressed. Once running it was OK. The EGR was also a problem on that car and if they fail or stick open for some reason, then starting will be very difficult.

Hi, frog

It what you're saying also available on the Siemens inection? From my understanding, those solving are for the Bosch injection.

Many thanks!

[AndreiNCS]

I mention that I've tested 2 injection pumps (5WS40018) , and the car shows no difference, it starts in that same hard way.