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Discussion Starter #1
Hi folks

Finally got my van back from being repaired, after a major breakdown at the start of the hols. It needed a reconditioned cylinder head, new gaskets, timing belt kits, new head bolts and crankshaft pulley kit, timing reset - topped off with fresh oil and filter and coolant...

Anyway, the first morning after getting it back, it wouldn't start (apart from a starter motor issue a while back, it's always started like a dream). Anyway, glow plug light goes out after less than 2 seconds, and I could hear a relay 'click' after about 5 seconds. Turns over quickly but not firing, with lots of white smoke coming out of the exhaust.

After going away and coming back and then slogging away with the key turned in the ignition, it begins to catch occasionally. If I keep faith it will eventually catch and carry on a bit longer and, just as the battery signals it's had enough it'll run. It then idles beautifully and seems to restart ok during the day.

Yesterday, after again getting it started...eventually, I noticed there was no relay click at all - all other symptoms were the same. There are no faults showing on VAGCOM.

I've had a search, but am getting confused as to whether it might be the glow plugs or a relay, or something else.

Any advice and links appreciated!
 

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Glow plugs
Fuses
Pump timing!(does it run well after a couple of minuets after its started)
Fuel filter
Air getting in fuel system
Diesel leak of pipes?

I have a similar problem which improves if I pull my cold start lever out, this tells me that it's likly to be the pump timing in my case.

What engine?
 

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sounds like glowplugs to me??
if the head has been of, my money is on the tag wire being left of the first glow plug? meaning that even though the relay is clicking, and the is 12v going down to the glowplugs.. if the tag wire is of... them there not getting any voltage!!
you need to check see if your getting 12v to each glow plug.. but if the tag wire is of.. you will soon see it!!
think on all the engines(1.9,2.4 and 2.5) the tag wire is fixed on the right most glow plug as you look at them??
or on the 5 cylinders it might be the second one in(cylinder number 4) its fixed to?

hope thats of some help??
 

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Discussion Starter #7
Thanks for the info folks, will have a check on the tag wire first off, and no, I don't have a cold start lever. Another point, is the fact that the relay no longer clicks significant?

Should have said it's a 1998 2.5 TDI ACV engine.
 

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Thanks for the info folks, will have a check on the tag wire first off, and no, I don't have a cold start lever. Another point, is the fact that the relay no longer clicks significant?

Should have said it's a 1998 2.5 TDI ACV engine.
yes it is!! either way start by checking to see if your getting 12v to the glow plugs.. then see if there's 12v coming out of the relay..
if there isn't, but there's 12v going in to it.. then its more than likely the relay at fault.
 

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Guys 2.5tdi's need very little glow in the winter let alone the summer.

Without glowplugs in summer it would still fire in less than 8 seconds.

Fuel pump timing is the first thing you need to check.
 

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i`ve had bother with the smaller filter on top of fuel filter before,one that fits into the filter was drawing air and allowing fuel to run back to tank, part is quite cheap so every 2nd filter change i chuck one on
 

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I had this on my 1.9td it turned out that the very end nipple of the bleed offs by the injectors should have been capped off, mine had come off causing air to be sucked back
 

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Discussion Starter #18
Thanks for the replies and a quick update...

Took a circuit tester to the glow plugs and associated connections, and there doesn't appear to be power going to them. Fuses seem ok.

I then took it to a garage as I need it fixed, and they were a bit vague, but have sent the ECU off to be tested/repaired, as they said it was to blame.
 

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Discussion Starter #19
Further update...

Spoke to mechanic and he said that all the glow plugs were dead. He mentioned that the ECU wasn't sending power to the circuit and that was why it was sent away for testing - does that sound about right?
 

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Didnt realise the glow plugs on the t4 were controlled by the ecu
I thought they were controlled by a timer relay
Still dont understand why your needing the heater plugs working on a 2.5 anyway
All the ones ive worked on and own start straight off the key no warm up time
I suppose they cant all be the same
Did your garage check your pump timing T:
 
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