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Discussion Starter #1
Morning All!

In an attempt to prove that my relative poor fuel consumption (27mpg, 1995 Aero Manual when it is usally 31mpg) is me not realising just how much mpg decraeses in the cold with short journeys.

The SID is currently showing 35.3mpg and last brim to brim check (mostly motorway showed 33mpg)

After 600 miles so far since Saturday, I have checked the spark plugs as recommended - does this look normal? - I do understand that most spark plugs are in focus ;)



This picture is from No 3 cylinder, 1 and 2 look the same but 4 has got more black soot around it (I had taken the picture before looking at all the plugs.)

Plugs have been in for just under 3000 miles, but during this time the car did spend 3 months not doing anything. I have checked the gap as best I can and it looks to be about 1mm. And plugs are the recommened BCPR7ES-11. And the car had some injector cleaner with a full tank on Saturday.

Am I worrying over nothing? As I am typing this I am thinking I am.

Thanks is advance

Bertie
 

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Bertie,

That plug looks about right given the difficulties of colour reproduction. I assume this is after a fairly 'spirited' drive. The colour description for plugs at the correct mixture is ' Donkey Brown'. You are showing no signs of oil fouling and weak mixture would be very white.

Paul; @ Kippen.
 

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Discussion Starter #3
Thank you Paul.

Another Brim to Brim fuel check showed 33mpg again so I am happy that the car is running well, on the engine side at least.


Bertie
 

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Bertie,

I find it very difficult to curb my enthuism for a full tank. Good intentions every time I fill up but the fun gets to me. 33 is pretty good, I assume this was another trip to Birmingham ? I generally get about 32.5 registered, 30.5 actual on motorway trips. That means cruising at about 82 and trying never to drop out of cruise. I've managed that all the way from joining the M9 at Stirling to the A66 cut off from the M6.

I guess running at lower speeds would improve the situation somewhat.

Paul @ Kippen
 

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I guess running at lower speeds would improve the situation somewhat.[/b]
:) I once did a 50 odd mile drive on the motorway from Exeter to Bristol at max 55 mph due to a failing DI pack, it was strangely relaxing (late at night so not too much botheration from overtakers) and I got 43MPG out of my 2.0lpt! (most of that went away in the last ten miles through town of course :( )

Cheers,
Robin.
 

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Discussion Starter #6
If I was worried about fuel economy I would have kept my Fiesta TDCi!

I just think that fuel economy is a good marker or how the car is running. I'm not bothered about mid 20s mpg if I have been 'playing' just when I think that I have been careful I like to see the benefit - hence agreement with Paul @ Kippen's comment about lower speeds.
 

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Bertie, you need to zoom in a bit closure to get a good focus on the plug (rather than the gravel!) ;-) but guess you didn't have macro mode!
To the point, the plug looks OK, and it certainly doesn't match the colour of the gravel :)
Normally all plugs should retain same colour, so I would keep a watch on plug 4 when you next change plugs, etc. Maybe worth adding a bottle of injector cleaner, perchance injector 4 is slightly fouled up - which would cause slight sooting.
 

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Discussion Starter #8
Bertie, you need to zoom in a bit closure to get a good focus on the plug (rather than the gravel!) ;-) but guess you didn't have macro mode!
To the point, the plug looks OK, and it certainly doesn't match the colour of the gravel :)
Normally all plugs should retain same colour, so I would keep a watch on plug 4 when you next change plugs, etc. Maybe worth adding a bottle of injector cleaner, perchance injector 4 is slightly fouled up - which would cause slight sooting.[/b]
I will keep an eye of plug 4 and put some injector cleaner in recently (ie about 400 miles before this photograph was taken!)

Thanks
 
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