I have a 2008 Renault trafic 1.9 diesel. If the vehicle has been stood for 12 hours plus, it won't start. The battery has tested fine, the heater plugs have been tested by an auto electrician who says they are fine.
I have noticed that the engine turns over fractionally but noticeably slower when cold and not starting. If I bump it (it fires straight away) then I could turn the engine straight off and turn the ignition and it fires no problem, and will fire perfectly for the rest of the day. The starter is also fractionally faster than cold all day also.
Pulling hair out, any bright spark know what this is ?

Neo, February 2012

Hi
Did you find out what was wrong with your van ? Mine is doing the same thing it's driving me crazy . I had new glow plugs etc still won't start when it's cold .

Mark, January 2013

When they tested the glow plugs did they take them out to test them or did they do them in the engine with a tester? Did they test the voltage supply to the glow plugs when the ignition is turned on and for how long do you get a voltage supply for before the relay cuts out? (do not always rely on the glow plug light on the dash) If not sure put a volt meter to the glow plugs and the negative to the battery earth to see how long the voltage goes to the them when the ignition is turned on and count how many seconds it lasts for, I bet it is longer than the dash light stays. Then try turning on the ignition and counting for the amount of seconds that the power supply goes to the glow plugs then do it again counting only half the amount of seconds then try starting the engine I bet it starts. If it does do this all the time for cold starting.

arizona kid, February 2012

Thanks for the quick answers guys. The strange thing is, once started I can turn the engine off immediately and it will crank faster and start within half a second. I don't thing the oil would have warmed up in 2 seconds ? The battery was installed an hour before post, it had been stored in the auto parts store which only opened 2 days ago. The battery is also 900cca and the manufacturer spec is 750cca. I'm lost any more suggestions ? Oh btw, have tried to get someone else to start whilst pumping the fuel syphon hand pump under the bonnet.

Neolithian, February 2012

My guess is that your oil is getting to thick with the cold. Looking in the news, Europe is experiencing a prety harsh winter presently.
I'm guessing that you are European as that vehicle is not available in North America.

You should use some high quality multigrade oil, like some 10W40 or even 5W40.
I live in Québec, and that kind of oil is always used.

Another thing to look for would be to install some battery heater, as your block heater can't warm up the battery.

Kuälinar, February 2012

Try using a set of jump leads from a running car when doing a cold start and see if that helps.this idea will just help eliminate a battery issue/slow cranking issue.Have you had a diagnostics done?.clamp fuel line overnight to see if fuel is draining back to tank whilst stood

Steve, February 2012