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post #11 of 21 (permalink) Old 06-09-2014, 07:40 AM
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Do a basic tune up.. air filter, change your oil / oil filter, fuel filter, cabin air filter, ect..

---------- Post added at 06:40 AM ---------- Previous post was at 06:40 AM ----------

Make sure your plugs are gapped correctly... .032 - .035


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post #12 of 21 (permalink) Old 06-09-2014, 03:05 PM
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Something must be wrong because I get better economy. I don't have VVT and regularly ride my gears to the redline.

I typically shift at 2k when cruising in the city though. Spin at 1400ish rpm in 5th at 60km/h.

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post #13 of 21 (permalink) Old 06-09-2014, 04:51 PM Thread Starter
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Quote:
Originally Posted by JacksonWilder3 View Post
Do a basic tune up.. air filter, change your oil / oil filter, fuel filter, cabin air filter, ect..

---------- Post added at 06:40 AM ---------- Previous post was at 06:40 AM ----------

Make sure your plugs are gapped correctly... .032 - .035
I had already changed all of those, as well as gapped the plugs (installed brand new ac delco's in may) I hadn't considered the O2 sensor... also thinking I may have to get my fuel injectors cleaned, as far as I know they have never been cleaned thoroughly, save for the occasional fuel injector cleaner solution through the tank... changed the fuel filter, air filter, cabin air filter last wednesday, filled her up and was at 20.3mpg at that fillup... currently DIC is reading average 18.3mpg and I have been lighter on the gas pedal that previously...
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post #14 of 21 (permalink) Old 06-09-2014, 05:40 PM
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It won't make a huge difference but make sire your tire pressure is good

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post #15 of 21 (permalink) Old 06-09-2014, 06:08 PM
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If the car never gets into it's closed loop fuel tables, you'll notice poor fuel economy and performance. Since your commutes are very short, it could be that the motor never reached normal operational temperature, and thus will ignore certain sensors and run off a preprogrammed rich table.

Pull out the plugs and check for carbon buildups. That's a good sign you're running cold.

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post #16 of 21 (permalink) Old 07-01-2014, 08:55 PM Thread Starter
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my last two fuel fill ups have been averaging 21mpg city... so after breaking in the new plugs and new filters, I would say that dirty filters, and bad spark plugs were the cause of my poor mpg, 21 is what I was averaging before I noticed a drop... I enjoy the sound this LAP makes... Got the oil changed, and had it serviced yesterday... when I left the chevy dealership, I noticed that it was alot louder under acceleration than it should be... pulled the car into the shop at work and turns out the service techs at the chevy dealership forgot to completely close the air box... closed it and it is quieter... so... the oil change should help bring my mileage up as well...
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post #17 of 21 (permalink) Old 07-10-2014, 06:31 AM
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Shifting at the lowest possible RPM without causing lugging in the next gear will give you best milage.
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post #18 of 21 (permalink) Old 07-15-2014, 05:30 PM
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That's true. 2k rpm is the magic number for me when I'm feeling frugal.

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post #19 of 21 (permalink) Old 07-16-2014, 03:23 AM
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Do you have any stored codes...??

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post #20 of 21 (permalink) Old 07-16-2014, 01:47 PM
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Hell! The most I ever got was 23mpg since I had the car! Ha! 83,000 miles. Cali Balt! Another 10,000 to 20,000 I am redoing the dumbass fuel filter set up! Putting on out of tank fuel filter on it!!
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