A6 2.5 TDI SE (1995) Starting issue

[M V E Pullen]

I am new to this forum.

I have an (old!) 5 cyl diesel A6 with a lot of miles on the clock. Overall, it has performed very well and not given me much trouble at all in 11 years. It still goes on very long trips with me!

It now objects to starting - particularly in the cold. I immediately thought glowplugs (and so did my local garage) and had the set replaced. This eased the problem to start with but it has now regressed - to the point where it churns for a very long time before firing if the temperature is low.

The glowplug warning light comes on for a few seconds and then goes out but it still doesn't like starting - which makes me wonder whether it is a control unit/timer issue.

Has anyone experienced this and is it easily solvable - or should I stop being mean and do what other (non-Audi!) drivers tell me, and have it "diagnosticked"? (The less charitable ones tell me I should get a new car!)

[jubbly]

Have you had the timing checked latley?

The belt can stretch and cause the timing to alter slightly.

Though my 1997 2.5 tdi doesn't like starting in the cold either and that has had new glowplugs to.

[M V E Pullen]

Jubbly
Thanks for your thoughts - I have been thinking about changing the timing belt as this one has done 50 - 60,000, so I'll probably get it done now.
I did get a tip about this starting problem from a local auto-electrician who suggested that the problem might be the thermostat switch at the block end of the top coolant hose. This is wired in the same colours as the glow plugs and "tells" the glow plug timer when the plugs are needed. I've replaced this (easy job - it's a little component but costs about £35 from Audi!!) and it has made a lot of difference to cold starting, but starting when semi-warm is still a bit tortured.
The test for this switch is, when starting the engine, to check how long the glow plug indicator light (coil) stays on for in cold weather. If it goes out in a couple of seconds the switch may be faulty. Disconnecting the switch (pulling off the plug!) should cause the indicator to light up for around 10 - 15 secs. I found the engine would then start ok.
Hope the thoughts are useful. I'll see whether a timing belt change makes any difference and report back - my bank balance may make this wait for a month or so though!

[jubbly]

Hi,

I have already changed this switch, though it only cost me £6 from europarts as the Audi price was extortionat, thought unless this is faulty to there is no difference to the time the plugs stay on, the longest has been 8 seconds at -2, not long enough in my opinion!