Cold starting issue - glowplugs?

[Escort2dr]

My A6 2.0tdi seems to have taken a lot more cranking to start in this cold weather, culminating this morning in about 10 attempts to start it before it finally fired and ran. Temperature was around -1 degC. The car starts fine after that.

Is this likely to be the glowplugs, or something more sinister? It has done 102K miles but I have never had this before on any of my A4s or the Passat before it (same engine - PD).

Any help would be appreciated. It's booked in for Friday but some ideas in the meantime would be good to prepare me for the inevitable bill.

[Tame Technician]

Is probably glow plugs yes, but it could be a loss of fuel pressure.

If you clamp the return fuel line, (near the filter the one with the temp sensor in line) this will artificialy raise the fuel pressure, if it then start ok, it was a fuel pressure issue. (injector seals, tandem pump, or even cylinder head)

If it still takes a long time to start its somthing else. (glow plugs, engine mangement etc.)

A number of stone cold starts and a pair of mole grips to test properly.

[Escort2dr]

Thanks for the input. I had wondered about fuel pressure, but I suppose I'm turning a blind eye to that situation in the meantime as I don't want to think about the cost. It'll be interesting to see if the RAC Gold warranty pays out if it is something serious like a pump or head.

Will have a go with mole grips tomorrow.

One thing I forgot to mention was the the problem seems to have been getting worse over the last few days. Previously it had started fine in much colder weather around Xmas.

[pacman1]

Older diesels need a decent crank speed to fire if the piston rings are naturally worn, is your battery fully charged?
In really cold weather I turn the ignition on, wait for the glow plug light to go out, repeat, then start .
hth.

[Escort2dr]

pacman1 said:

Older diesels need a decent crank speed to fire if the piston rings are naturally worn, is your battery fully charged?
In really cold weather I turn the ignition on, wait for the glow plug light to go out, repeat, then start .
hth.

I tried to do this this morning, letting the light go out, then repeating. Eventually it sounded like it was going to 'catch', then it did fire a couple of times after that.

I did think this approach would compensate for knackered plugs, but also wonder if this would lead to the increased fuel pressure if there was a leak.

Can only wait until tomorrow and see what happens. How easy is it to change the glowplugs and is a special socket required?

[Tame Technician]

If it turns out to be glow plugs (dont hold your breath) You need to take the cam cover off, they're inside. But they its just a pop off electrical connector and a 10mm socket, but for gods sake dont drop anything in there.

[Escort2dr]

This morning at 4.5 degC, started first time but a bit rough. Looks like it might well be the plugs then.

Thanks for your assistance TT.

Edited by Escort2dr on Tuesday 2nd February 09:28

[Tame Technician]

If the plugs are bad enough it will log a fault code, also if its the relay/contol unit that power them.

It wont log any codes if its fuel pressure though, PD engine management doesnt need to know the fuel pressure so there are no sensors to pick up on a problem.

[cindacone]

HI tame technician
my A4 flags glow plug errors and all 4 have been changed. is it any easy job to change the relay and or controller to help stop the light coming on for emission warnings? unless its something else.....
Thanks in advance
Cindacone