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(another) MPG FIX (possibly)!!

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Old Jun 1, 2004 | 07:26 AM
  #1  
guy321's Avatar
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Humpin legs and takin nam
 
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From: Clearwater, Fl
(another) MPG FIX (possibly)!!

OK.. I've been getting 15mpg VERY VERY VERY steadily with my normal driving routine. I only go to the same 4 or 5 places repeatedly, so my trips don't vary much.

I typically fill up at 1/4 tank wich is right at 170miles's at 11* gallons.

So I was about 2/3 through my current tank. The gauge was very predictable and was set to give me another 170mpg by 1/4 tank. Every notch from 1/2 to the 2/3 march was giving me exactly 10miles.

Yesterday, I cleaned my MAF with 97% Isopropyl Alcohol. I just removed the sensor and poured some of the stuff on there from both sides, then let it dry.


So far i've my gauge looks like I'm set for 180miles to finish out the 1/4 tank. I probably won't know for sure till I fill up.

The reason I decided to do this is because I had had an aftermarket airfilter on there before and I believe some oil had gotten on the MAF..

Just some food for thought.
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Old Jun 1, 2004 | 07:49 AM
  #2  
310Guy's Avatar
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Keep us posted. I hope it works.
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Old Jun 1, 2004 | 05:11 PM
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Interesting. Let us know what happens.
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Old Jun 2, 2004 | 03:54 PM
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From: Dracut, MA
Guy, what are you doing out here in the Garage?

Back to the Lounge with you!

:p
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Old Jun 2, 2004 | 10:38 PM
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^ That's exactly was I was thinking. Guy321 in The Tech Garage??? Hmmmm.
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Old Jun 3, 2004 | 01:30 AM
  #6  
JeRKy 8 Owner's Avatar
Stuck in a love triangle
 
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From: Miami, FL
How comeyou never drive to empty?
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Old Jun 3, 2004 | 09:33 AM
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The owners manual suggest filling at 1/4 tank. I do it, but occasionally it doesn't work out... like today.
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Old Jun 3, 2004 | 09:58 AM
  #8  
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Did you run out of gas today? I was on fumes myself. The fillup was 14.11 gallons and cost me $29.90.

My most expensive fillup in my 13 years of driving
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Old Jun 3, 2004 | 10:40 AM
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I didn't run out, but it will be a bit below 1/4 tank since I had a 30 minute commute to work this morning w/ a 1/4 tank. Gas here is 2.07 /gallon now (hell of a lot lower than the Cali and the rest of the world!). I'll probably be in the mid $20 range. I wish Dodge would hurry up and release the Slingshot so I could decide if it or a motorcycle would be in order...
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Old Jun 3, 2004 | 01:13 PM
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i couldnt break 15 mpg if i drove highway the entire time. with the windows up, the a/c off, granny shifting, cruising @ 60 on a downhill.... i mean seriously, this sucks! I sit here in absolute awe and disbelief when i see some people posting 20+ mpg. and getting over 300 miles out of a tank of gas, Im lucky to break 200 miles on a tank. I have 3600 miles on the car. and have owned it since birth. gas has had absolutely no improvement from day one to now. Mazda says 18/24 mpg. we get 13/15 mpg. I pay friggin $28-$30 ever 3 days. thats $250-$300 a month. screw that. I WANT A SOLUTION. I WANT A FIX. I WANT AN EXPLANATION. FROM MAZDA. IF EVERYONE CALLS / E MAILS MAZDA... THE PEOPLE WHO ARE EXPERIENCING THE SAME ISSUE AS I AM. OUR VOICE WILL BE HEARD. AND MAZDA WILL BE FULLY AWARE THAT THE PROBLEM IS WIDESPREAD. AND A FIX COULD BE AROUND THE CORNER.. OR ATLEAST SOME FORM OF REISBURSEMENT.. WHO KNOWS..www.mazda.com... e mail them. I DID!
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Old Jun 3, 2004 | 01:33 PM
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Glad you learned how to copy / paste Hollywood.
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Old Jun 3, 2004 | 01:44 PM
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Hollywood Hall...

Check out my charts at
https://www.rx8club.com/showthread.p...0&pagenumber=2

There is hope!

As soon as my car hit 5000 my mileage improved GREATLY with no changes in driving habits!
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Old Jun 3, 2004 | 01:49 PM
  #13  
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guy you said you only go to 4-5 places and thats it .so which 4topless bars are you going too .the other stop must be mc donalds
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Old Jun 3, 2004 | 02:12 PM
  #14  
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Originally posted by HollywoodHall
i couldnt break 15 mpg if i drove highway the entire time. with the windows up, the a/c off, granny shifting, cruising @ 60 on a downhill.... ...
Do you have the "M" flash? If not, get it!
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Old Jun 3, 2004 | 02:19 PM
  #15  
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Humpin legs and takin nam
 
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From: Clearwater, Fl
I finished my last tank with 15.89 mpg..

which is the highest i've ever gotten with 100% city driving..

Keep in mind, I only ran maybe 1/8 of a tank before filling up.. so homefully I'll see improvement with the new tank!

I always fill at 1/4 tank now because I ran out of gas 3 times in one year once and i vowed never to let it happen again

I never go to strip clubs unless i'm dropping off my friends to work.

I'll go back to the lounge now
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Old Jun 3, 2004 | 02:25 PM
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Thews8
 
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From: Oregon South Coast
Originally posted by FONZIE
Did you run out of gas today? I was on fumes myself. The fillup was 14.11 gallons and cost me $29.90.

My most expensive fillup in my 13 years of driving
out here i would love to pay that little :P
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Old Jun 3, 2004 | 02:27 PM
  #17  
thew's Avatar
Thews8
 
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From: Oregon South Coast
P.S. try filling up my 36 gallon tank on the 4x4 at $2.78 a gallon .

Holy F,,, i just did the math if i fill up my 4x4 with a full tank of 91 it will cost me $100.08 !!! shees.. guess i wont do that ever again ..
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Old Jun 3, 2004 | 02:35 PM
  #18  
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Thews8
 
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From: Oregon South Coast
Originally posted by guy321
I finished my last tank with 15.89 mpg..

which is the highest i've ever gotten with 100% city driving..

Keep in mind, I only ran maybe 1/8 of a tank before filling up.. so homefully I'll see improvement with the new tank!

I always fill at 1/4 tank now because I ran out of gas 3 times in one year once and i vowed never to let it happen again

I never go to strip clubs unless i'm dropping off my friends to work.

I'll go back to the lounge now
You know your gas guage is not perfect ? it will give you diffrent readings for diffrant reasons. I say this because if you are going down to a 1/4 tank everytime you fill up then this may be part of the reason you think your getting such bad mpg. Theres more gas left in the tank, and fuel lines then you think. Trying running down till the gas light just comes on.

Or be brave and carry two, 2 gallon can's of fuel with you, drive the 8 till it stops running. put the 2 gallons in the tank, dirve it till it stops. then figure your mpg and use the second can to get home. You will find the true number once and for all!

I had to do this in my 4x4 because the tank readings are not accurate below 1/4 tank. Now I know excatly when it will run out.. And at 7000 lbs you cant really push it anywhere ...

my 2cents
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Old Jun 3, 2004 | 02:44 PM
  #19  
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From: Clearwater, Fl
I know the gauge is not completely accurate. I am dividing the number of gallons pumped by the miles driven. That gives me an accurate MPG for what I have driven.

It may give me a more accurate MPG to drive to the entire tank. However, I'm not in the habit of doing that.

Also, Using the same method for all my fillups also gives me an accurate base for comparison.
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Old Jun 4, 2004 | 07:01 AM
  #20  
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For whoever asked, refilling at the 1/4 tank mark will greatly increase fuel pump life. The fuel pump is submerged in fuel in the tank and uses the fuel as coolant for the electric motor. If you run it below a 1/4 tank it will run very hot, which will shorten it's life.
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Old Jun 4, 2004 | 11:23 AM
  #21  
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You should never run your gas tank that close to empty...you pull the scum from the bottom of the tank into the engine. ...also agree with the preserving life of your fuel pump. Just my .02 cents
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Old Jun 4, 2004 | 12:36 PM
  #22  
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So, any news on how well this is working? Maybe a note on progress thus far to get the thread back on track?
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Old Jun 4, 2004 | 12:45 PM
  #23  
guy321's Avatar
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Humpin legs and takin nam
 
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From: Clearwater, Fl
Too easrly to tell yet. Ill give an update after the tank is done.
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Old Jun 4, 2004 | 04:12 PM
  #24  
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Thews8
 
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From: Oregon South Coast
Originally posted by Red8
You should never run your gas tank that close to empty...you pull the scum from the bottom of the tank into the engine. ...also agree with the preserving life of your fuel pump. Just my .02 cents
Filter!

theres a filter screen on the intake.. and then a fuel line filter before the injectors. !! hogwash..

run that tank down to the light.. thats why it is there.. if not Mazda would make the light turn on at 1/4 tank :P
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Old Jun 4, 2004 | 04:15 PM
  #25  
thew's Avatar
Thews8
 
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From: Oregon South Coast
and a pump is a pump is a pump.. even if it sucks air your not going to to run it till it burns up.. its not possible. with no fule you car shuts down .. then you turn off the key ..

and even if you did leav the key on and the pump was trying to sux air !! and did start to get hot.. the fuse would blow..

These are old wives tales, some of witch used to be true. but with todays fuel systems you can run the tank down to at least the light with no fear of damage whatsoever.
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