I have an 03 plate 1.9 TDi Superb with 230K on the clock. Had it since new. Today the engine refused to fire up. It tried to start as normal but just "died" within a couple of seconds. Subsequent turns of the key just have the engine turning over with no sign of it starting or "catching" as if it's about to start. The thing is this is the second time it has done this in the last two weeks. Each time after it's been left over 24 hours standing. The last time it happened I just left the car a few hours and a friend came round to take a look. While he was there and we tried again and it fired up with him doing nothing.....typical lol.

So this morning it has done it again. Exactly the same symptoms. Exacty the same scenario. When it died on the first try I just knew it wasn't going to start. But leaving it a few hours this time has not helped. The only other thing that happened on both occasions is that while turning the engine over a few times the red oil warning light came on. This only happened once on one attempt at starting up. It didn't happen on each try at turning over. Seemed strange that the oil light would come on when the engine isn't running. Maybe this is a red herring but it did happen on both breakdowns.

The car has run perfectly in the two weeks between breakdowns. Started first time and run smoothly.

Any ideas? I can get the AA out in the morning as I have Homestart.

Edited 17 October, 201015 yr by DBrown67

Release the fuel pipe from the outlet of the filter and check the lift pump supplies fuel for about 2 secs after key "ON". At your mileage, check tank strainer if no delivery.

If you have fuel, change relay 219 in the engine ECU box. It will probably have broken (fatigued) soldered joints. (A VAG perennial for the last 15 years).

Then VAGCOM.

rotodiesel.

The oil light behaviour is normal for this system - you don't get to see the output directly from the pressure switch - only VAG's interpretation of what you should see.

Edited 17 October, 201015 yr by rotodiesel

Got the AA out to it this morning. First thing they did was check the fuel supply. That was fine but on refitting the pipe the car started straight away. Seems there was an air lock in there. Must be that air is getting in there slowly over a period of time. If the car is used each day there's not enough time for it to be a problem. AA guy reckons it could be an injector stuck on open, or something as simple as a loose pipe connection or replace fuel filter. Last two problems cheap and cheerful, just hope it's not injector related.

It will not be an injector - the symptoms would be entirely different and they don't "stick" anyway.

If you are getting air in the fuel, check the two "O" rings on the plastic Tee fitted to the fuel filter. If it's a genuine "VAG" fuel filter it may well be Chinese - these can leak air at this point. If the car is due for a filter change, buy a Mann & Hummel or Bosch filter from a factor and fit it. It will come with 2 replacement "O" rings, one black and one blue. Fit them correctly and oil the joint before reassembly. Prime the filter when you have fitted it.

Don't take the pipes off the Tee - it will break. Just undo the "Mickey mouse" clip.

rotodiesel.