FIAT Doblo 06' 1.3 MultiJet 62kw/84hp - Engine long start

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Wed 31 Aug 2016 13:39
FIAT Doblo 06' 1.3 MultiJet 62kw/84hp - Engine long start - 3uga

Hi !

I'm having a long start problem with my car. It doesen't mater if it's a cold star or not, the car starts after a longer cranking time than other cars. Bought the car with the problem existing on purchase.

Thank you!

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Wed 31 Aug 2016 17:36
FIAT Doblo 06' 1.3 MultiJet 62kw/84hp - Engine long start - hardway

As it's an 06 I'm going to presume it cranks over at over 200 RPM yes?

if not then the battery/starter system is suspect.

If it does crank at higher than 200 then suspect the coolant temperature sensor.

I'd plug it in to my scanner and read the engine temp that the ECU is actually "seeing"

If the ECU live data temp reading is of then the fueling is off.

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Wed 31 Aug 2016 19:58
FIAT Doblo 06' 1.3 MultiJet 62kw/84hp - Engine long start - focussed

This POS engine is known to burn it's glow plugs out - replace.

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Wed 31 Aug 2016 21:32
FIAT Doblo 06' 1.3 MultiJet 62kw/84hp - Engine long start - 3uga

I've seen that the coolant temperature sensor is showing the temperature but did not check if it changes as engine warms up. I"ll check glow plugs as well but don't see how these might be a problem since the hard starting is persistent even as the engine is warmed up.

I'll get back as soon as I do these checkups

Edited by 3uga on 31/08/2016 at 21:33

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Thu 1 Sep 2016 16:46
FIAT Doblo 06' 1.3 MultiJet 62kw/84hp - Engine long start - hardway

Engine cranking speed?

It's really important.

Diesels need at least 180 rpm but over 200 is better.

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Thu 1 Sep 2016 18:55
FIAT Doblo 06' 1.3 MultiJet 62kw/84hp - Engine long start - elekie&a/c doctor

Forget the glow plugs.As Mr H says,cranking speed and fuel pressure are critical for a crd engine to start.

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Fri 2 Sep 2016 09:52
FIAT Doblo 06' 1.3 MultiJet 62kw/84hp - Engine long start - 3uga

The cranking speed si above 200.

I've checked the coolant temp sensor and it works ok.

Edited by 3uga on 02/09/2016 at 09:56

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Fri 2 Sep 2016 10:01
FIAT Doblo 06' 1.3 MultiJet 62kw/84hp - Engine long start - 3uga

Next, I will check fuel presure. The obd scanner shows be 30000 kpa at idle and a constant of 800, 30 minutes after engine shutdown. I think i have to connect a a pressure gauge the check to be shure..

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Fri 2 Sep 2016 19:49
FIAT Doblo 06' 1.3 MultiJet 62kw/84hp - Engine long start - hardway

Cranking speed is fine and fuel pressure is over the 200 bar needed for starting so I'd be looking now at air.

If the air flow measurment is off then it would match your symptoms.

Have you tried uncoupling the Air flow meter then trying to start it?

Many diesel will ignore the AFM reading and substitute a default reading from memory when it's unconnected.

If it now starts up then ....

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Wed 7 Sep 2016 20:40
FIAT Doblo 06' 1.3 MultiJet 62kw/84hp - Engine long start - 3uga

Coolant temperature is ok. Fuel pressure is 300bar at idle and up to 1100 at full throtle. I don't know the exact specs for thsi fuel pump.
I've heard these engines have a common problem with these hard stats. A tip I got was to check to see if the fuel regulator works properly.

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Wed 7 Sep 2016 21:45
FIAT Doblo 06' 1.3 MultiJet 62kw/84hp - Engine long start - elekie&a/c doctor

Forget the crd parts for the moment.Have you done any basic mechanical checks, like cylinder compression and valve timing.It is very common for the timing chains to wear on these.Also,have you had the injectors performance tested for flow and spray pattern?

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