gt tdi warm starting problem....

[Pete H]

just had a search through and couldn't find anything similar

my T plate gt tdi starts fine from cold, but once you've done a run in it, like getting home from work, then go straight back out, it turns over for a good 10 secs or so before eventually firing.

anybody have this? any ideas people?

cheers, pete

[richandhazel]

just had a search through and couldn't find anything similar

my T plate gt tdi starts fine from cold, but once you've done a run in it, like getting home from work, then go straight back out, it turns over for a good 10 secs or so before eventually firing.

anybody have this? any ideas people?

cheers, pete

I've had this exact problem. I fixed it but never really put my finger on exactly what was causing it. Some of the things that may have contributed are:-

I had air being drawn into the clear section of the fuel pipe. You could see a bubble there.
I replaced the battery.
I altered the timing slightly.

The replacement battery failed within the year and the fault started to come back as the battery failed. Seems weird as you would think the battery would be more likely to cause problems when the car has been left a while and is cold. Maybe thats just coincidence.

[Pete H]

just had a search through and couldn't find anything similar

my T plate gt tdi starts fine from cold, but once you've done a run in it, like getting home from work, then go straight back out, it turns over for a good 10 secs or so before eventually firing.

anybody have this? any ideas people?

cheers, pete

I've had this exact problem. I fixed it but never really put my finger on exactly what was causing it. Some of the things that may have contributed are:-

I had air being drawn into the clear section of the fuel pipe. You could see a bubble there.
I replaced the battery.
I altered the timing slightly.

The replacement battery failed within the year and the fault started to come back as the battery failed. Seems weird as you would think the battery would be more likely to cause problems when the car has been left a while and is cold. Maybe thats just coincidence.

funny that as it had a cambelt change recently!!!

i have seen some air in the clear pipe to be honest, how did you fix it, just replace the pipe?

[richandhazel]

Ah, now would that cambelt change happen to coincide with when the problem started?

The air being drawn in was fixed by simply replacing the spring clamps on the fuel filter. A couple were getting quite weak. 

Here is some info that I came across whilst trying to diagnose my problem, most of it from http://www.tdiclub.com/:-

http://tdiclub.com/TDIFAQ/TDiFAQ-8.html#b

What are the symptoms?
If it starts easily when cold, but seems to need excessive cranking to start when warm (like when you stop for five minutes at Tim Horton's), you need a new battery. I know, this sounds crazy....but it cures the problem. The computer looks for 300 r.p.m. during warm cranking before turning on the fuel, and an old battery has problems reaching that threshold. I had that problem a few years back, and once the new battery was installed I could immediately hear that it was turning over faster. It started instantly too. Many here have had that problem, and it always seems to work!

[Pete H]

Hi all a little update!!!

So far i have changed the glowplugs, temp sensor and the relay (109), it starts 'better' now, but as always im never satisfied, when i changed this all it started great, let the car get to normal running temp, a few times as the temp gauge was rising id turn it off and on again and it's start on the dot, but when the temp gauge was bolt up right (normal running temp) and a switched it off it would have trouble again.

i did notice though alot of air was travelling along the clear fuel pipe, didn't effect the car when it was running, but once i knocked it off i could see the large bubble travel to the top of the hose (highest point), tried started and it'd have trouble again, no missing, just winding over for longer than i would think.

What's next, any ideas? Should i check all the fuel pipes from the tank plus the ones in the engine compartment and replace all the clips? I know i said about the cambelt being replaced but i runs so well when it starts (and i don't wana strip it down as the engine mount has to come off )

cheers, pete

[richandhazel]

When was the last time the fuel filter was replaced? You may find that the seals on the T piece have perished if it hasn't been done for a while (you get new ones with the replacement filter). The T pieces can also get damaged so worth a look at that.

The timing may well need looking at if it hasn't been fine tuned using VAGCOM. You will only get it roughly there by locking the pulleys. Whenever a timing belt is replaced the timing will need fine tuning using VAGCOM.......just envolves adjusting the fuel pump, not a strip down. See the TDIclub FAQ sections link that I sent you for more info