2003 4.0tdi - will not start when hot - rickA8
Hi All
I've just bought an A8 4.0TDi which runs like a dream, but when its hot it refuses to start. When cold it will start every time.

I'm guessing its a sensor somewhere on the case telling it not to start because it thinks its too hot but where?

Also the temp gauge sits at 50 which has to be wrong.



{header amended to remove duplicate entry of make/model & year/engine details as this gets automatically filled in from the compulsory boxes you already filled in}

Edited by Dynamic Dave on 24/11/2008 at 12:29

2003 4.0tdi - will not start when hot - Screwloose

Can't you take it back? This is why it was sold off.

Has someone removed the thermostat to try and mask the hot starting fault? Can you check the actual coolant temperature with a laser?

That sounds like low rail pressure - which is not nice on one of these. You'll need to get a specialist diesel engineer to plug it in and have a look - could be a cracked injector or a worn HP pump.
2003 4.0tdi - will not start when hot - rtj70
I was waiting for screwloose to reply before I did. I too thought that this was sold because of a fault. And on such complex cars/engines the repairs might be costly. Could be something simple but can you not go back to the garage that sold it?
2003 4.0tdi - will not start when hot - sanjx
Did you ever get this sorted? Im having the same issue with my car, probably the same car haha