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gas consumption problem

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  #1  
Old 02-13-2005 | 08:45 PM
payam's Avatar
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Default gas consumption problem

yo

03 civic si. i have horrible gas consumption ya'll. so, everyone's telling me it's the way i drive it, but no! for a week, started w/full tank and i shifted at 2500-3000 rpm, no flooring, easy starting and stopping, etc. three days later, half-tank. three days! now is that even possible? that my bad gas consumption has something to do w/my car? yeah, anyways, what do u all have to say about it? anyone w/the same problem?

peace, holla back
 
  #2  
Old 02-13-2005 | 09:00 PM
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How far do you drive each day? What mods done to car?
 
  #3  
Old 02-13-2005 | 11:19 PM
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Both of those are good questions, but for the most part, intake and exhaust mods should slightly increase mileage. If there's nothing obvious about your driving patterns like short trips, or lead feet, consider changing your O2 sensor (front, not rear). If it's getting tired, and thinks you're running lean, it'll richen the mixture. Bad mileage is the obvious side-effect of this, but a shortened lifetime of a fairly expensive catalytic converter is the other.

How many miles on the car, and have you ever had an internal coolant leak?
 
  #4  
Old 02-13-2005 | 11:25 PM
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Default RE: gas consumption problem

wait... ther is a REAR O2 sensor? for what?
 
  #5  
Old 02-13-2005 | 11:26 PM
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Default RE: gas consumption problem

Maybe because there alot of traffic and you have to stop and go a lot???

Or maybe you just think that you have half gallon left when you only have 3 really. Atleast for my 94 ex the gas needle may be point at half tank but for really i have like 7 or 8 gallon left. Today my needle were right on the E redline on the fuel gauge and I went to get it fill up full and it turn out that i can still drive another 60 miles(2 gallon) with the needle directly on E.

You can also buy a new pulley if you wanna better you mpg while adding better acceleration.
 
  #6  
Old 02-13-2005 | 11:28 PM
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Most modern cars (MOST) have 2. The first in a 4 cylinder or transverse 6 will be in the rear exhaust manifold or downpipe. This is for correcting the AFR. The second will be behind the O2 sensor in the intermediate pipe. This is an OBD2 requirement. This sensor is for emissions only. It tells the PCM if the cat is doing it's job properly. This second O2 has no effect on mileage or performance.
 
  #7  
Old 02-14-2005 | 01:24 AM
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Default RE: gas consumption problem

im willing to bet my rear O2 is faulty. BTW it was good talking to ya Bill.
 
  #8  
Old 02-14-2005 | 01:41 AM
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Remember, IF you have a rear (O2) it won't hurt performance OR efficiency. It only tells the PCM if the cat is good or bad.
 
  #9  
Old 02-14-2005 | 01:42 AM
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Default RE: gas consumption problem

o well to hell with that
 
  #10  
Old 02-14-2005 | 01:44 AM
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Default RE: gas consumption problem

Sorry to rain on your parade, bud. Most O2's generally need to be replaced for performance at about 50k miles. If your's is there, it wouldn't hurt to be proactive.

EDIT------the O2 in our exhaust manifold, not behind the cat
 


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