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aftermarket HIDs causing reduced mpg??

Discussion in 'Gen 2 Prius Fuel Economy' started by boo510, Dec 2, 2010.

  1. boo510

    boo510 New Member

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    hi i drive a 2008 gen 2 prius and im starting to suddenly lose gas mileage after i hooked up my DDM HIDs 6k 35w w/ relay harness. before i was getting about 43mpg and now im getting like 35-39mpg.

    there's 60k miles on my car, tires r fine, oil change recently done, and no other mods to my car. can anyone help me solve the issue? is it possibly the HIDs because its wired to the battery?
     
  2. F8L

    F8L Protecting Habitat & AG Lands

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    Not likely. Unless there is a constant drain on the electrical system which is keeping the engine running when it should be turning off, I would suspect the recent drop in temperature and the increased moisture on the roads in your area.
     
  3. kenmce

    kenmce High Voltage Member

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    The headlights should pull no power when off. An easy test would be to drive the same route at the same speed with the lights on and off.
     
  4. Paul58

    Paul58 Mileage Miser

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    I thought HID were supposed to draw less power than normal headlights. I think it's the drop in temps that's causing your drop in gas mileage.
     
  5. qbee42

    qbee42 My other car is a boat

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    Perhaps the OP shouldn't have used the 1,000,000 cp lamps. ;)

    Tom
     
  6. boo510

    boo510 New Member

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    last year around this time i didnt get a dramatic drop of gas mileage like this though
     
  7. F8L

    F8L Protecting Habitat & AG Lands

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    If you are worried you loss of mpg is related to your new headlights then I would start monitoring how long your engine stays on. If it is staying on longer than norm
    al and not turning off at lights then you may have a problem. When your headlights are off there should be no drain. I bet you drive with them on during the day to show them off too? Or you just drive a lot at night?
     
  8. boo510

    boo510 New Member

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    uhh i still drive the same amount day and night regularly and no i dont leave my headlights on during the day. during the day i do seem to notice that i do lose some power as well
     
  9. macmaster05

    macmaster05 Senor Member

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    Boo it's definitely the weather. I was getting 54mpg a month ago. Last week I filled up and got 47.0mpg. Sucks!
     
  10. boo510

    boo510 New Member

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    i hope its just the weather. im so sad im losing mileage and having to refill the tank more often