Cranks fine but won't start after coldest day

[MoreTea]

After the coldest day of the year where I live, it got to -7C 

 

Went to start the Roomster, it cranks fine, but no kick in at all. Just chugga chugga chugga till the battery flats

 

I placed my phone on the Fuel Feed Pump lid to record the sound when I turn the starter key to the first light - it makes this noise before I turn the key fully to crank:

 

yow! What's that crunching noise? Is that normal ?

 

Coincidence? What do I do next ?

 

 

[MoreTea]

It momentarily sounds like there are metal bits in a food blender

 

Please help.

[SuperbTWM]

Does the rev counter register a speed when cranking? what is the fuel level? when was the fuel filter last changed? Have you confimed you are getting fuel to the tandem pump?

 

Lift Pump sounds fine to me, bit of air going through the line initially but otherwise couldn't hear anything abnormal

[MoreTea]

Hi, the rev counter does not move immediately when cranking. After about 2-3 seconds the rev counter moves up a little to show as about 500 rpm ?

 

1/2 a tank of fresh fuel

 

Only had car a few weeks. No history when fuel filter renewed.

 

I note that when cranking the engine, the Oil pressure symbol comes on with a buzzer. 

Please excuse my newbie, how do I most easily verify fuel to the tandem pump? (I have no ramps just very basic kit)

 

Appreciate you helping, my dogs are panicking now...

 

 

 

[KenONeill]

51 minutes ago, MoreTea said:

After about 2-3 seconds the rev counter moves up a little to show as about 500 rpm ?

Is there any evidence of white smoke from the exhaust at this time?

[MoreTea]

Hi Ken, thanks.  I got a friend to help. She reports no smoke or anything seen from the exhaust during a long crank of the engine

[KenONeill]

34 minutes ago, MoreTea said:

She reports no smoke or anything seen from the exhaust during a long crank

Ok, probably not duff glowplugs then.

[MoreTea]

If I look to see if diesel is going at the Inlet and out at the Outlet at the fuel filter (when cranking), is that the next logical step ?

[MoreTea]

I had another go.  Cranked the engine for a long time... much longer than before.. it started to splutter. The odd splutter here and there.... I thought the battery would drain first...

 

Then it kicked into life !

 

I'm letting it run on idle for a while until I figure out my next step

 

I don't want to take a car to the country that's likely to fail again the same way if I can ameliorate it a bit now

 

Any ideas what the issue was? (parked after the coldest night) How I might address it ?

 

thanks 

[bobspark]

I would say check oil sump level with buzzers going off? Check battery is giving out 12.1 volts or more after heater plugs have gone off. After my heater light goes off battery is showing 10 volt for another 30 seconds after which it goes up to 12.1 volt and then car will start.

[KenONeill]

54 minutes ago, MoreTea said:

Cranked the engine for a long time... much longer than before.. it started to splutter. The odd splutter here and there.... I thought the battery would drain first...

 

Then it kicked into life !

Cancel my previous; check the glow plugs because that sounds a lot like burnt out glow plugs.

[SuperbTWM]

6 hours ago, KenONeill said:

Cancel my previous; check the glow plugs because that sounds a lot like burnt out glow plugs.

IF the car has had little maintenance then the glow plugs will probably all be dead, that said unless its about -20 the 1.9 lump will start without any glowplugs so i don't think this is the cause at all.

 

Regarding the oil pressure warning : when you crank for a long period the car has expected the car to start so is warning you of low oil pressure, but this is obviously genuine as the car still hasn't started.

 

If you have only just got this car it could literally be anything stopping it from starting, who knows what issues it has but its more than likely going to be fuel related, either the lift pump intermittently not working, air in the fuel lines causing air in the system somewhere or possibly injector wiring.

Edited 5 January, 2023 by SuperbTWM

[J.R.]

I seem to recall some stupid system on one of the TDi engines that would prevent the injectors from operating unless the cranking RPM exceeded a certain threshold, I call it stupid because the PD engine will start on a lazy 1/4 of a turn at minus 40°c with all glowplugs failed, but it wont start if it has that stupid system unless it can whip over beyond the threshold.

 

Some tuning companies had found a way to disable it.

 

Hopefully someone can advise if its relevant to your engine, I thing it was the PD engine of about your year.

[SuperbTWM]

24 minutes ago, J.R. said:

I seem to recall some stupid system on one of the TDi engines that would prevent the injectors from operating unless the cranking RPM exceeded a certain threshold, I call it stupid because the PD engine will start on a lazy 1/4 of a turn at minus 40°c with all glowplugs failed, but it wont start if it has that stupid system unless it can whip over beyond the threshold.

 

 

 

 

That's just a hot starting issue, on a cold start the injectors should fire up no matter the cranking RPM. (providing the CTS isn't reporting the wrong temperature that is)

 

And yes it was a very stupid part of the programming which forced many to re-new their starter or get the map fixed

Edited 5 January, 2023 by SuperbTWM

[J.R.]

Thanks for that, it explains my confusion, I was thinking to myself you have got something wrong as the PD starts so well in 1/4 turn, it would not have even generated a speed signal.

 

Good observation regarding the CTS which is a known common failure.

[MoreTea]

Just to update, been starting absolutely instantly. In fact never had a diesel start so enthusiastically.

 

Put of bottle of Comma D-Tox through just to clean everything.

 

'touch wood'

 

Thanks !!!