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Discussion Starter #1
Hi guys, i posted a thread about my bad mpg a couple months ago. Im still averaging around 16 mpg highway and city mixed, went to the mechanic and they said my o2 sensors are good, vanos seals good, etc. The mechanic suggested i might want to look at my fuel filter, could that diminish my mpg that bad? I really need an answer, thanks guys
 

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If it's clogged up it could hurt. Really, with 130K miles, you should do all of the typical tune-up items since they're due and that should bring it back up. (this is based off the fact that I didn't read your other thread and presume these items haven't been done yet).
 

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fuel filter air filter plugs oil etc
 

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Discussion Starter #4
I bought the car in january and the service records dont show a tune up, that i will prbly do soon
 

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If it's clogged up it could hurt. Really, with 130K miles, you should do all of the typical tune-up items since they're due and that should bring it back up. (this is based off the fact that I didn't read your other thread and presume these items haven't been done yet).
Agree. On both my cars I have changed the fuel filter at 100k. This can certainly be a culprit in your poor mpg. Did you do a tune-up at 100k? If you did I would not suspect spark plugs either. Change that fuel filter ASAP, open it up and see what the old one looks like, it will tell you a lot.

Just read your new post. Do spark plugs, fuel filter, oil change/filter, and make sure your VCG is still good while you're at it.
 

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I guess the other obvious question is: How are you determining you gas mileage? Cluster readout or an actual method of miles driven versus fuel used?
 

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Yeah buddy, rollin' like a bigshot. No but really, are you sure you ain't tryin' to hard to keep up with traffic? :eeps:
 

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Change that fuel filter ASAP, open it up and see what the old one looks like, it will tell you a lot.

Disclaimer:
Do this right away or else the gunk will seep out. Within 15 minutes or so, take a grinder and make two cuts (180 degrees apart) down the length of the filter.














:evil:
 

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Discussion Starter #9
Agree. On both my cars I have changed the fuel filter at 100k. This can certainly be a culprit in your poor mpg. Did you do a tune-up at 100k? If you did I would not suspect spark plugs either. Change that fuel filter ASAP, open it up and see what the old one looks like, it will tell you a lot.

Just read your new post. Do spark plugs, fuel filter, oil change/filter, and make sure your VCG is still good while you're at it.
thanks man i will do that soon, just got an oil change btw
I guess the other obvious question is: How are you determining you gas mileage? Cluster readout or an actual method of miles driven versus fuel used?
im looking at the trip readout and calculating it when i fill up my car
Yeah buddy, rollin' like a bigshot. No but really, are you sure you ain't tryin' to hard to keep up with traffic? :eeps:
no, but here in hawaii traffic can get pretty ridiculous :censored:
fuel filter air filter plugs oil etc
well i have to look into the fuel filter and plugs, just got an oil change and put in a new air filter two months ago
 

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its not like HI has a lot of hwys - so, my guess is the larger tires/wheels are lower mileage, the stop and go of HI and possibly a heavy footed driver
 

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im looking at the trip readout and calculating it when i fill up my car
:thumbup: Just making sure we weren't missing something here....I've known a few to read the cluster MPG readout and say they can never get better gas mileage (when really its a weighted average and inaccurate at that!).
 

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Discussion Starter #12
its not like HI has a lot of hwys - so, my guess is the larger tires/wheels are lower mileage, the stop and go of HI and possibly a heavy footed driver
When i had my stock 16 inch wheels on, I got the same mileage, so there might only be a drop of maybe 1/2 mpg. There is alot of stop an go in hawaii, but i dont usually drive during rush hour, and i drive the car pretty easy, highest i rev it is 3500 rpm
 

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try doing the traditional math for calculating the mileage

fill tank and drive a couple of days

fill again, then divide the mileage driven by the additional gas added..
 

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Discussion Starter #14
^I did that, i think i was averaging 20mpg on the highway so not bad
 

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both of my 330s, 6 spd, (one with 3.62 LSD and one with 3.15 LSD), and ESS TS SCd, cams, headers, etc...

both get around 19-20 in city and about 27-30 on hwy

I drive hard
 

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I used to get horrible mpg in my 323 vert until I did a complete tune up (aka everything mentioned in this thread) and now I can get 33-34 mpg at 60mph hwy and 28 mpg at 80mph hwy; and around 19-21 city if I'm driving like a sane person
 

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Discussion Starter #18
Thanks guys, i need to do a tune up asap
 
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