Fiat Doblo Cargo - Smoking when cold

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Tue 12 Jan 2021 05:30
Fiat Doblo Cargo - Smoking when cold - Damon Turver
Hi guys, hoping someone can help a man tearing his hair out.

A year ago I bought a Fiat Doblo for work. The van starts every time and runs very well, but when at cold and idle it produces a lot of white smoke (and a strong smell) and ‘hunts’ a bit at idle- smoke starts about 30-45 seconds after starting motor. When driving or when it’s up to temp no smoking at all (although there is still a slight smell which a friend of mine also has with his Doblo).

With lockdown coming a couple weeks after purchase the garage I bought the van from hasn’t been helpful at all and simply referred to my 12 month warranty that isn’t worth the paper it’s written on, especially with no obvious sign as to a faulty part. I have taken it to several different mechanics and had several areas looked at. There are no fault codes showing.

- Gasket heard tested and fine
- EGR valve cleaned thoroughly after it was running at above suggested pressure % on mechanics computer.
- Full service done including changing the fuel filter.
- Went to a diesel specialist who told me all the injectors where fine at the time and lots of Doblos do that.
- The latest guy (deals in cleaning of EGRs etc) suggested an injector could well need changed (as when running he had his computer on it and one of the cylinders was running at 2.8-3.2ish whilst the others at small deficits of around -0.1 (I’m not mechanically minded so not sure what that measures.)
He changed the injector last night only for the problem to still be exactly the same.

I’m starting to get stressed with it now. MOT due in a couple days and worried it will fail on emissions/smoke unless they test it when warm obviously.

Anyone had similar issues or any suggestions what so ever?
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Tue 12 Jan 2021 14:06
Fiat Doblo Cargo - Smoking when cold - sandy56

Try using SHell superdiesel or similar for a while. It can take a few days and miles to make a difference. Run the car on the motorway and get the engine hot. Or get some diesel cleaner additive and add to the tank but superdiesel is better.

Could be an injector problem- you can get the injectors checked/tested at a diesel specialist. If necessary get them reconditioned or buy new. good luck

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Tue 12 Jan 2021 19:27
Fiat Doblo Cargo - Smoking when cold - DavidGlos
For the MOT, take it for a decent run and present it fully warmed up for the test. Ask them to do the smoke/emissions test first. Make sure you give it some welly (once it’s fully warmed up) on the way to the test centre to blast any crud out of the system.

Full beans to the red line in 2nd gear a couple of times should do the trick.

Edited by DavidGlos on 12/01/2021 at 19:28

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Tue 12 Jan 2021 22:19
Fiat Doblo Cargo - Smoking when cold - Railroad.

A diesel engine is a compression ignition engine. Diesel fuel will not ignite unless it is vapourised and reached a temperature of around 500°C. White or light grey smoke is an indication of unburned fuel, possibly due to low compression on one cylinder or lack of air.

It could also be a coolant problem, possibly a cylinder head gasket or a cracked cylinder head.

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Mon 10 Apr 2023 08:07
Fiat Doblo Cargo - Smoking when cold - Paulo247
Hi I have similar problem? Did you ever get it fixed?
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