Ford Fiesta - Increased fuel consumption following mot

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Wed 10 Nov 2010 23:14
Ford Fiesta - Increased fuel consumption following mot - Richt1976

I had my car put through the mot last thursday and the only thing it required was a new nearside front wheel. I filled the car up the same day.

Since then I have noticed a sharp increase in fuel consumption. The main issue being for the first 5 or so miles (It will often register as having used 15 or so miles worth of petrol on the trip computer over this distance) of any trip.

I have checked the tyre pressures and corrected these, but the issue remains. There were no other notes on the mot paperwork apart from the new tyre. I am using the same source for getting the petrol as the previous few times I have filled up.

Would anyone have any suggestions as to what could be causing this? Is it likely to be something the mot mechanics may have done, or is there a possibility it is just concidence that the standard of petrol I have filled up with this time is of poor quality? Any help gladly appreciated!!

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Thu 11 Nov 2010 08:17
Ford Fiesta - Increased fuel consumption following mot - Falkirk Bairn

Check the brakes - MoT test stress tests the handbrake and brake calipers/shoes / pads.

Following an MoT my then 5 year old Honda Civic would hardly accelerate and the rear wheels were both warm / hot. Eased off handbrake cables and all was well.

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Thu 11 Nov 2010 15:04
Ford Fiesta - Increased fuel consumption following mot - Richt1976

Thanks Falkirk

I have taken it to a local garage this afternoon (not the one that did the mot!) and apparently there is nothing wrong with the brakes, either wear or handbrake wise. So am back to square one!

It does seem worse when the engine is cold, if that makes any difference?!

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Thu 11 Nov 2010 17:17
Ford Fiesta - Increased fuel consumption following mot - injection doc

Just reset the average MPG first.

When the car would of been in for MOT it may of been running for 25 mins and upset the average MPG.

As an MOT tester used to get loads of people say they used more fuel after an MOT but its normally just because the average on the trip has dropped!

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Thu 11 Nov 2010 18:16
Ford Fiesta - Increased fuel consumption following mot - Richt1976

Thanks Doc

Unfortunately I dont use an average MPG, but have a 'count down' type display instead. Essentially the problem is that my 22 mile drive to work is sometimes registering as having used 40 miles worth of petrol on the countdown. I know these arent hugely reliable, but its annoying nonthe less!

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Thu 11 Nov 2010 22:51
Ford Fiesta - Increased fuel consumption following mot - Peter.N.

The temperature has dropped considerably in the last few days, at least it has here, that could affect it, particularly if you can't initially get a bit of speed up to warm the engine.

Is your engine running at normal temperature, a faulty thermostat can affect the fuel consumption.

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Tue 23 Nov 2010 17:53
Ford Fiesta - Increased fuel consumption following mot - Richt1976

Thanks Guys

I took the car in to a local garage that i trust and they ran a diagnostics test on it, which came up completely clear!

The only thing they could suggest was that it could be the change in the weather. I guess I'll only know come spring!

Edited by Richt1976 on 23/11/2010 at 17:54

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