I have a 2000 Si, with a shade under 71k on it. Bought it used from a dealer, mostly highway miles, from what I understand. I can barely get 240 miles out of a tank of gas.

Parts I have replaced so far-
Plugs
Wires
Fuel Filter
PCV Valve
Disty Cap
Disty Rotor
Oil has been changed also.
Royal Purple in the tranny.

checked the fuel regulator on the fuel rail, vacuum seems to be ok there, as idle speeds up when the vacuum line is disconnected from the intake manifold.

I can't think of anything else it could be. Also, sometimes the car can be sluggish in first gear..

Only thing i have left to think it is, is o2 sensors.. any other ideas to try before i drop 100 bucks on o2 sensors?

 

What about air filter change?

 

its clean, checked it the other day.

it will be replaced with an AEM soon, but hell i figure i could try that.

i purchased the car from a dealer on OCT. 29th of 03. i presume that was replaced.

also, i forgot to mention. awhile back, the car threw a code saying "bank 1 rich" essentially its saying that the system was running rich, so i kind of figured it was o2 sensors.. but not sure.

 

Same here.. i use to get like 300 miles.. now only about 230. My car had some down time when i was waiting for my rims to come in, so i did a valve adjustment and now i have **** for miles.

 

you guys ever hear of SeaFoam? I've used it before.. it really helps. just take a vaccuum line and let it suck it up into the intake manifold.. it'll choke a bit.. and you'll see white smoke coming out the rear, but that's just carbon deposits getting burned up from the catalyst (seafoam) mixing in..

it helps.. every 3 months or so..

 

Perhaps your timing belt is off by a notch or two.

 

going easy on the gas pedal!! SAVE BIG GAS

 

that could be my problem to

 

What size wheels do you have or are they stock? When I went from 14's to 17's my gas mileage went from about 340 a tank to 250.,

 

where could I get this seafoam?

 

i went to the same size tire so nothing changed there.. also.. im still not that comfortable with the hole seafom thing.

 

run on stock wheels or anything lighter with 195 tires.

 

If it threw that code its most likely an O2...although I can't say for certain since I don't have a book with the codes (my own car has the older OBDI system)

 

yeah, the car is 100% stock, minus an airbox hack and the above non OEM replacement parts..

i am thinking its the o2.. just don't wanna spend all the dam money. and then drop the b-pipe which is ******* hell to get off i bet..

ugh, probably easier to find a used header for the dam thing.

actually, better than seafoam is BG44K

i just need to find a bottle of it now. a shop here swears by it.

anyone have a good hookup on parts? or places to go?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Ape &raquo;</TD></TR><TR><TD CLASS="quote">i went to the same size tire so nothing changed there.. also.. im still not that comfortable with the hole seafom thing.</TD></TR></TABLE>


There's nothing wrong with seafoam, it's really good if your having trouble passing emissions. I've personally had it help me pass for 3 years in a row. It's the only thing that works for me anymore

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by csprague &raquo;</TD></TR><TR><TD CLASS="quote">If it threw that code its most likely an O2...although I can't say for certain since I don't have a book with the codes (my own car has the older OBDI system)</TD></TR></TABLE>

Well your in luck my friend check out my ecu code thread in my signature. comes in real handy

 

that would he handy..

but i have an EK.

 

could also be if your area uses reformualted gasoline for cold weather. They use that watered down B.S. here in california and my gas milage takes a big **** on me. If you cant find bg44, techron is also very good.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by zberger &raquo;</TD></TR><TR><TD CLASS="quote">yeah, the car is 100% stock, minus an airbox hack and the above non OEM replacement parts..

i am thinking its the o2.. just don't wanna spend all the dam money. and then drop the b-pipe which is ******* hell to get off i bet..

ugh, probably easier to find a used header for the dam thing.

actually, better than seafoam is BG44K

i just need to find a bottle of it now. a shop here swears by it.

anyone have a good hookup on parts? or places to go?</TD></TR></TABLE>

seafoam is actually quite good.. you can pour it in your gas tank, in with your oil, or in your intake manifold.. you'll see more results if you pour it down your im.. and then a week later, put one in right before you fill a full tank of gas.. napa, autozone.. pretty much any auto store will have it..

 

I thought I read some where that the gap between the spark plug and the socket you put it into has to be just right, if it is not then your gas mileage goes to hell along with other things. Anyone else heard this before, or is it just some old wifes tale?