Audi A8 (1994 - 2003) - 01 2.8ltr petrol (APR) will not start

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Mon 3 Mar 2008 21:31
01 2.8ltr petrol (APR) will not start - aah for starters
Dear All

Anyone had an Audi that would not start when the engine is mildly warm ?

My A8 always starts from cold and from hot, but sometimes will not re start if it's only been running for a few miles and it's really trying my patience. Had to abandon it today and let it go cold, thereafter started easily.

Is there an ECU upgrade or fix or maybe something like a dodgy sensor that I should replace. The car is a dream to drive, but if I can't rely upon it, then its going to have to go!

Any help, thoughts, ideas or indeed experiences would be great


Engine details edited in

Edited by Pugugly on 03/03/2008 at 22:41

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Mon 3 Mar 2008 21:38
My Audi Will Not Start - Pugugly
Moved over from Discussion - can you tell us what the engine and year variant is ?
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Mon 3 Mar 2008 22:12
My Audi Will Not Start - aah for starters
Certainly,

It's a 2001 2.8ltr petrol, engine code APR
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Mon 3 Mar 2008 22:36
My Audi Will Not Start - Screwloose

Changing the coolant temperature sensor would be a good place to start.
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Mon 3 Mar 2008 22:53
My Audi Will Not Start - aah for starters
Thanks,

The engine temp gauge is a bit dodgy, sometimes reads then shows nothing. Could the two be connected ?
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Mon 3 Mar 2008 23:29
My Audi Will Not Start - Screwloose


It's a combined sensor; so very possible.
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Sat 8 Mar 2008 19:18
My Audi Will Not Start - keep the heap going
If it is a Bosch system up to late nineties, then the hot start is usually controlled by a relay which is black and in the engine compartment. This prevents the system overfuelling and when the relay is dead, the engine overfuels when starting from warm/hot and engine effectively floods and it takes repeated turns and sometimes the only way to start it is to leave it, or hold the throttle open which is not great. If the car does catch, the emissions warning light goes on due to the excess fuel being cleared from the system.
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Sat 8 Mar 2008 19:51
My Audi Will Not Start - Screwloose
If it is a Bosch system up to late nineties then the hot start is
usually controlled by a relay which is black and in the engine compartment. This prevents
the system overfuelling and when the relay is dead the engine overfuels when starting from
warm/hot and engine effectively floods and it takes repeated turns and sometimes the only way
to start it is to leave it or hold the throttle open which is not
great. If the car does catch the emissions warning light goes on due to the
excess fuel being cleared from the system.


What??
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Sat 15 Mar 2008 11:19
My Audi Will Not Start - aah for starters
Thanks very much for the advice.

I replaced the engine coolant sensor (£16 part) last Saturday and the car has behaved perfectly since.

Fingers crossed it's fixed
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