CDI mpg improvement

Discussion in 'Engine' started by Leabrooks, Apr 12, 2014.

  1. Leabrooks

    Leabrooks Hardcore MB Enthusiast

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    Just thought I'd share this. I've been using diesel Redex and two stoke oil for the last few months (both from Wilko's, £2 for the Redex, £3 for the 500ml T2 Jaso FB grade) both will do two full tank fulls and have been achieving a consistent 10% improvement in economy and a much quieter cold engine and more responsive when booted. My daily trip to work (at 10 miles from home) is now 47/48 mpg up from 42/44 mpg (and much less sometimes). Can't explain why maybe its acting as an upper cylinder lubricant and decoker but it works. Might take a tankfull before the benefits. Non dpf car by the way (CLK 270 CDI). Cheaper than silly priced diesel 'super' grade per fill up and it works. Redex and 2T, try it.
     
  2. LTD

    LTD MB Club Veteran

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    Yep, one of THOSE !!!
    I've seen similar improvements in the economy of my E220

    No additives, just warmer weather.
     
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  3. ItalianTuneUp

    ItalianTuneUp Hardcore MB Enthusiast

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    Good stuff! Weirdly, I saw the opposite, i.e. a reduction of economy after adding Millers ecomax additive to a tank full of Shell fuelsave diesel (normally I use Asda diesel). Any ideas?
     
  4. ItalianTuneUp

    ItalianTuneUp Hardcore MB Enthusiast

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    Is it recommended to add two stroke oil to improve running?
     
  5. geraldrobins

    geraldrobins Hardcore MB Enthusiast

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    Ive also seen an inprovement over the last 2 months due to weather and nearly 10%
     
  6. E270 Owner

    E270 Owner Hardcore MB Enthusiast

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    Summer Diesel ?
     
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  7. geraldrobins

    geraldrobins Hardcore MB Enthusiast

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    Higher temperatures not just diesel as my mpg varies on the same tankful and temperatures have varied on my morning journeys from 4-12 this week.
     
  8. OP
    OP
    Leabrooks

    Leabrooks Hardcore MB Enthusiast

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    I do agree it could be the warmer weather helping with the improved mpg, but i must say I'm impressed with the mpg...if i can crack 50mpg on the OBD after 10 miles I'll be over the moon!
     
  9. Dieselman

    Dieselman Banned

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    I've seen the exact opposite in the new steed. It was struggling to achieve better than 34mpg average, two tanks of Shell with Millers now sees and easy 40+mpg and averages of 44mpg are attainable.

    This is in the last two weeks, so not temperature or summer diesel related.
     
  10. ItalianTuneUp

    ItalianTuneUp Hardcore MB Enthusiast

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    Yes, I don't know what caused the drop in economy, but I changed to shell and put the Millers in at the same time so I have no idea what happened. I'll have to wait and see after a couple more tanks full.

    Don't know if it could affect economy, but I noticed that the air duct leading to the air filter box had become detached. Could this have an effect on economy?
     
  11. Dieselman

    Dieselman Banned

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    Possible, as the engine would be ingesting hot air, but unlikely to make much difference.
     
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  12. ItalianTuneUp

    ItalianTuneUp Hardcore MB Enthusiast

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    Thanks, I'll see if it makes any difference now that it has been re-attached. Economy fluctuations, disregarding the winter/summer differences, are probably mostly caused by lead foot syndrome, wind speed & direction, temperature, air pressure & density variations. But I do find it interesting nevertheless how much variation there can be. Also, lights on/off, air con on/off, stereo on/off etc will have a small effect too, I suppose.
     
  13. Dieselman

    Dieselman Banned

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    I ran tests on my regular route with CC set to 74mph, also on local journeys the economy was shockingly poor.

    I noticed the car had a sooty rear bumper and black exhaust tip, but no visible smoke when driving. This is no longer an issue.
     
  14. ItalianTuneUp

    ItalianTuneUp Hardcore MB Enthusiast

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    Was that the Millers magic or hooning it?
     
  15. Dieselman

    Dieselman Banned

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  16. ItalianTuneUp

    ItalianTuneUp Hardcore MB Enthusiast

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    Sooty stuff coming out of exhaust.
     
  17. Dieselman

    Dieselman Banned

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    I can only think it is the Millers as I really caned it a few times and there was no improvement.
     
  18. ItalianTuneUp

    ItalianTuneUp Hardcore MB Enthusiast

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    Ok then.

    That reminds me, after tipping a load of Millers into the tank, I must have failed to close the bottle correctly and the damn stuff leaked out onto the carpet in the boot and made a dreadful stench which shows no sign of shifting... :eek: :doh: :wallbash:

    Luckily it seems not to be noticeable in the cabin of the car, but I should probably think of a way of cleaning it out.
     
  19. OP
    OP
    Leabrooks

    Leabrooks Hardcore MB Enthusiast

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    I forgot to say I thrash the nuts out of the car on a steep hill (about a 5 in 1) on the way home from work, as i worked out hitting the hill slow or fast makes no difference to the mpg but it sure cleans the crap out when floored uphill after half a mile....and some shocked divers behind as I hit warp speed (ok 60mph officer) from a sharp 20mph corner at the bottom of the hill, so no run up just torque.
     
  20. OP
    OP
    Leabrooks

    Leabrooks Hardcore MB Enthusiast

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    Took the car up to Eyam today (from Alfreton via Chesterfield and Baslow) on A and B roads, came back through Chatsworth Park picked up heavy traffic at Darley Dale/Matlock (surprise lol) on the A6, then B roads up to Holloway and Crich (and steep hills) and achieved an OBD of 47.7 for for a round trip of 52 miles...high of 49.4 going through Chatsworth after about 40 miles. Loads of Sunday drivers out (pensioners) so point and squirt where possible....over the moon..I'm sticking with the 2T and Redex (or Millers etc) mix...engine was as sweet as nut, pity about the rear end roll (see my other thread).
     

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