I just had Fog Lights installed on my 2012 Civic Sedan4DR...I was getting 40MPG even going 80 MPH and now I can't get past 32.9MPG for my life...even holding 60-65 mph...so what gives, how did I lose so much MPG...I'm thinking the bumper did not get put back on properly??? also....the Fog lights....so they ONLY go on with headlights???? My acura allowed my fog lights to go on w/o the headlights being on....sure need some help on all this.....any ideas...I want my 40MPG back!
Fog Lights Installed- MPG issues
- Thread starter Jules
- Start date
KennyGS
How may I help?
Wow! Foglights causing a 17.75% reduction in gas mileage? 
I can't imagine the bumper could cause this.
I can't imagine the bumper could cause this.
clevrname
Well-Known Member
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A lot of the MPG readers aren't very accurate. Most of them read high and once the car is broken in more, they become more accurate.
And unfortunately with Honda, they only allow your fog lights to come on with the headlights. I know i've read DIY on 8th gens to bypass that and be able to come on separately.
And unfortunately with Honda, they only allow your fog lights to come on with the headlights. I know i've read DIY on 8th gens to bypass that and be able to come on separately.
- Staff
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when you're talking about your mpg - are you talking about a reading on the dash, or actual mpg by calculating it at the pump? Have you been using a different gas station or anything? Are your tires all showing the right air pressure? The only other thing I can think of is your air filter, but I can't picture that becoming so clogged during one tank or something.
As clevrname mentioned, the fogs are setup to come on with your headlights in the stock form. Let us know
As clevrname mentioned, the fogs are setup to come on with your headlights in the stock form. Let us know
- Thread starter
- #5
I took it to the dealer, they showed me the bumper is lined up, fogs only come on with headlights...bummer.....gas mileage 40 mpg before...squeeezing 34 after....no improvement....told dealer i would be back in 1 week..2027 miles on vehicle...mpg was continually improving from beginning..about 2 mpg on average per day...and then....fog light installation....go figure....
WHAT...could be so much different to cause this....next thing...crawl under one that hasn't been changed....see if I'm missing something...??? a shield or seals on the bumper....????advise please....tks
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are you going off the miles per gallon showing on the dash, or calculating your miles by the # of gallons you actually are pumping?
If you aren't doing it by miles divided by the # of gallons you pump, do it this way the next time you fill up. Reset your trip meter, and see what your mileage is. The meters on the dash have proven to not be 100%. I've seen some people report them being as bad as 10% plus or minus off. People tried to get a recall on other makes because their mileage was not the same as reported on the dash meter.
Reset your trip meter, and fill up your tank. When it comes time for your next fill up, take your # of miles (say 350 miles and divide it by the # of gallons you put in your tank - say 10 gallons). You'd then say you achieved 35mpg on that tank. Do that for at least a few tanks and see if your milage changes much. Granted city driving vs. highway is going to alter your milage.
If you aren't doing it by miles divided by the # of gallons you pump, do it this way the next time you fill up. Reset your trip meter, and see what your mileage is. The meters on the dash have proven to not be 100%. I've seen some people report them being as bad as 10% plus or minus off. People tried to get a recall on other makes because their mileage was not the same as reported on the dash meter.
Reset your trip meter, and fill up your tank. When it comes time for your next fill up, take your # of miles (say 350 miles and divide it by the # of gallons you put in your tank - say 10 gallons). You'd then say you achieved 35mpg on that tank. Do that for at least a few tanks and see if your milage changes much. Granted city driving vs. highway is going to alter your milage.
versys chris
Well-Known Member
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Hi Jules, I can tell you why your readings are off. When the dealer installed the fog lights, they had to disconnected the battery to do so. In the process the MPG stored in the computer got erased. So now you are starting new. If you didn't have your MPG readout reset at every fill up and were keeping it going since the day your bought the car, then it is easy to get to 40 MPG after a while and even a few miles in town won't change that display, since it is doing the math over the 2027 miles you drove, hence very little change. My father in law just did the same thing on his new 2011 Toyota Corolla and the display hardly ever changes. Once I asked when he reset the last time he said 1800 miles (3000km) ago! There you have it. The best way to do the MPG is to actually calculate them the way webby said, since those electronic gauges aren't that accurate to start with, especially if you are driving a lot of short distance, since the computer updates only so often.