Anyone else had 999.9 mpg from a 3L V6

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tomcourtney
1.8 8v
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Location: Stafford, UK
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Anyone else had 999.9 mpg from a 3L V6

Post by tomcourtney »

Is this linked to my 'running lumpy' as if on 5 cyl .
If you've had either of these symptoms what was it ?
Thanks in advance...
Tom
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mjb
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Re: Anyone else had 999.9 mpg from a 3L V6

Post by mjb »

It means you're moving without using any fuel. It happens when you've got your foot off the accelerator with the revs high enough - either coasting downhill or engine braking. The ECU stops injecting fuel into the engine. Happens in most modern fuel-injected cars
<steve_earwig> I think this forum is more about keeping our cars going with minimal outlay than giving our cars more reason to go bang
tomcourtney
1.8 8v
Posts: 45
Joined: Mon Jun 09, 2008 5:58 am
Location: Stafford, UK
Contact:

Re: Anyone else had 999.9 mpg from a 3L V6

Post by tomcourtney »

I'm getting 999.9 mpg all the time, even accelerating. I realise this is a fault just don't know what is causing it.
Tom
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mjb
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Location: Stoke

Re: Anyone else had 999.9 mpg from a 3L V6

Post by mjb »

I'm not entirely sure on D9s, if it's not a loose connector on the back of the display, i ain't got a clue other than a BSI screwup
<steve_earwig> I think this forum is more about keeping our cars going with minimal outlay than giving our cars more reason to go bang
tomcourtney
1.8 8v
Posts: 45
Joined: Mon Jun 09, 2008 5:58 am
Location: Stafford, UK
Contact:

Re: Anyone else had 999.9 mpg from a 3L V6

Post by tomcourtney »

Going to try a soft reset as found on another forum tomorrow, then change plugs with an inlet manifold gasket (is this dry ?)



Soft reset
From hereon in the soft boot procedure will be described as the '3 Minute Rule'

PROCEDURE FOR BATTERY DIS-CONNECTION (The 3 Minute Rule)
Whenever a vehicle battery has to be dis-connected, switch off all equipment,
interior lights etc, close the doors leaving the drivers window open.
Switch off the ignition and remove the key and any DIAG equipment.

Wait a full 3 minutes before disconnecting the battery.

The BSi must be allowed to go to SLEEP i.e. into "power save mode". Do not
operate any equipment on the vehicle during this time. Remember, even
opening the bonnet will wake the BSi on a vehicle fitted with alarm.

If the battery is under the bonnet, open the bonnet first and leave it up. 807
batteries can be dis-connected through the drivers window, remove floor cover
first. (note, Pics are under the passenger seat)

ALWAYS disconnect any DIAG equipment and do not operate any plips from
other vehicles during the 3 minute waiting period.


PROCEDURE FOR BATTERY RECONNECTION
Unless otherwise instructed by Product Service, you must always
carry out the following procedure, often referred to as a "soft re-boot", to
minimise the possibility of the BSi corrupting its own software when
reconnecting the vehicles battery supply.
Ensure the procedure for battery disconnection has been adhered to and
importantly all BSi functions were switched off with the drivers window left
down.
1 Close all doors
2 Remove ignition key if left in ignition
3 Reconnect battery. DO NOT open any doors
4 Wait 10 seconds
5 Switch on headlights through the drivers window (you will hear a "bong") (note: Snap-on says Side-lights)
6 Switch on ignition then start the vehicle and check system functions

NOTE: Upon reconnection, if any vehicle function controlled by the BSi i.e .
interior light is switched on,the internal operation of the BSi has the potential
to spike or corrupt its configuration and software program......
============================================================

This makes it difficult to fault find the BSI circuit board live. The danger seems to be whilst trying to find a simple indicator fault we could end up with a vehicle off the road or windows stuck down due to software corruption.



Any other suggestions appreciated
Tom
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