Glowplug/relay issues

[steve valentine]

Afternoon gents.

Struggling to start from cold, has new battery and glowplugs.

Once warm, starts first turn of the key, when cold, can take up to 10 seconds of cranking.

Glowplug light doesn't put in an appearance, not even for a second as is usual.

Now, what tells the glowplug relay that it's cold and time to play? or could it be the relay?

Vehicle is oct 2002 MK1 2.0 HDI 800.

[muply]

relay maybe mines been playing up in the cold 2

[Ol'Jeffers]

I think its likely that a temperature sensor sends a voltage to the ECU and that activates the relay to switch on the pre-heaters. Possibly. cratch:

[Rustscrat]

Hi, I think on the mk1's there is a "post heat thermal switch" (1157) but I will check with your engine.tudy:

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Hi, I think on the mk1's there is a "post heat thermal switch" (1157) but I will check with your engine.tudy:

As far as I can tell if your engine is the dw10 TD then it does not have the above thermal switch. I think it is turned on via the Bsf from the coolant temp sensor (Like OJ said). Is your temp gauge reading zero when the ignition is turned on?

I got to say though on my mk2 with the same engine it's got to be bloody cold before the I get the preheat light on. Only seen it on once so far this year!!!

[wertyu2007]

i would say relay yes .

mine had same symptoms as yours last year after changing glowplugs ,
if you hot wired glowplugs in the mourning direct from battery for 4/5 secs it would start as per normal , i did this for week but got fed up with opening bonnet every day .

timing it with a multi meter it was only hold plugs on for 1/2 secschanged relay and fine .
it was proper cold last year as well though i would be nice to have a plug heater switch for cold days to give it a bit extra.

[steve valentine]

Well, I've ordered a relay, it will be here monday, which is no good, as I'll be working in wales until thursday, so I'll change it thursday and let you know how I get on.

[steve valentine]

The relay came today, very quick delivery from GSF Car parts!

Fitted.

Fixed?

No

Although the glowplug light did come on for maybe 1/2 a second and then went off.

Next step, temperature sensor, already ordered, will update when it arrives and is fitted.

[Rustscrat]

The relay came today, very quick delivery from GSF Car parts!

Fitted.

Fixed?

No

Although the glowplug light did come on for maybe 1/2 a second and then went off.

Next step, temperature sensor, already ordered, will update when it arrives and is fitted.

Hi, just to let you know mine came on this morning and only stayed on for 1/2 second.
Starts up on second turn though. Have you got Lexia ?? maybe one of your injectors is playing up or condensate in fuel??cratch:

[knobblywobbly]

On the 2.0 engine the glowplugs will come on for only half a second when the coolant temp is 0 degrees.
Mine takes a bit of cranking to start when it's cold too.
You may be hunting a problem that doesn't exist.

Sent from my GT-I5700 using Tapatalk

[andy-womble]

On the 2.0 engine the glowplugs will come on for only half a second when the coolant temp is 0 degrees.
Mine takes a bit of cranking to start when it's cold too.
You may be hunting a problem that doesn't exist.

Think you may be correct there, it is the nature of the beast and mine is exactly the same, mine also seems a bit slow cranking from a cold start but ok once run. Occasional puff of white smoke on cold start but clears after a couple of seconds...