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Old 23rd May 2010, 22:04   #1
fergy05
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Default increasing MPG on a CDTi

guru's

what mods/changes can be done to increase MPG on a CDT?

obviously controlled driving is a must but what else?

ie air intake mod - does it help?

ta

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Old 23rd May 2010, 22:08   #2
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May I ask if you have a Manual or Autobox?
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Old 23rd May 2010, 22:13   #3
rrobson
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a good question would be what are you getting now? no point speaking hypothetically when we dont know where to start
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Old 23rd May 2010, 22:19   #4
fergy05
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its a manual matey

i havent actually brimmed the tank yet but my MPG comes across as good to me i dont have a problem im literaly trying to find out what helps and what hurts.

All these modifications are posted all over the forums but nought really on how much they will affect the MPG and as im penny pinching at the moment every little helps
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Old 24th May 2010, 11:34   #5
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People say getting a knackered thermostat fixed should add a few mpg. As a related question, will a faulty theromosat still reduce mpg in the heat of summer?
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Old 24th May 2010, 11:50   #6
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Check the running temperature using Diagnostic mode test 7. You really need it to run at 90-100C. Most diesels run at 88-90C with a good stat. If you find it's less than 80C, that's one reason for poor mpg. Replacing a defective thermostat is a very effective way of gaining 5mpg or so.

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Old 24th May 2010, 11:57   #7
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basic things help like a light right foot,keep windows/sunroof shut at all times,no roof boxes either,keep air-con off,make sure tyres are correctly inflated,doing the air intake mod and running a ron box on the correct setting should also increase mpg as torque will be improved doing away with the need to keep changing up and down gears,a de-cat will also help as it stops back pressure in the exhaust system,if you can get a hold of yesterdays sunday times there is a very interesting article on improving mpg in the "in gear" motoring section
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Old 24th May 2010, 15:29   #8
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By the time you have done all the "mods" you may/may not gain a few mpg. But it will take many many many miles to get your outlay back.
...
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Old 24th May 2010, 15:32   #9
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Quote:
Originally Posted by James.uk View Post
By the time you have done all the "mods" you may/may not gain a few mpg. But it will take many many many miles to get your outlay back.
...

Yes but your grin will be bigger...
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Old 24th May 2010, 15:35   #10
Dave Goody
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Quote:
Originally Posted by Rolled1 View Post
basic things help like a light right foot,keep windows/sunroof shut at all times,no roof boxes either,keep air-con off,make sure tyres are correctly inflated,doing the air intake mod and running a ron box on the correct setting should also increase mpg as torque will be improved doing away with the need to keep changing up and down gears,a de-cat will also help as it stops back pressure in the exhaust system,if you can get a hold of yesterdays sunday times there is a very interesting article on improving mpg in the "in gear" motoring section
Keep windows and Sunroof shut at all times, Don't use air con?

The weight you will lose by sweating will give you at least 2 mpg
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