you guys must be horrible at math or just have lead feet to be getting 10 or 12mpgs . i cant see how thats possible in a civic. i get worried when mine drops anywhere below 30mpgs. i think i would stop driving it if it went below 20 let alone 10 or 12. you two both need to go buy a bike and forget driving.

 

Believe me I didn't trust it at first, but after a few fillups after only driving 100 miles I do now.
Thanks for the pictures so far, I am slowing figuring out what hoses are wrong and where to hook them.
a few pictures of a b18a would be great, the area that I need to redo the hoses I think are around the charcoal filter, the FI, the map sensor. After looking at other pictures and some diagrams, I think my stuff is hooked up really wrong. Not sure if that would have a big effect on how much gas the engine used, but it can't be good for it. Gonna have to wait till the middle of next week till my o2 sensor gets here and see if that helps.

 

Ok, I just hooked up my vacum hoses the 'right' way I think. I didn't have any more lose hoses. I start it up and it sounds better, but the rpms jump up to 3000. I try to turn the idle speed down and the lowest I can get it is 2500. Is there a problem with maybe using two small of a spliter, not letting enough air move? If I can't fix this will have to put it back to the way it was to drive it, as I don't think it would be good to drive a car that idles at 3K.

 

ok a typical civic has a max capacity of almost 12 gallons of gasoline, everytime i fill my gas tank i get barely 120 miles to the tank, therefore 120/12=10 stfu asshole.

 

His point is just to state that 12mpg in a civic/crx regardless of engine is really poor. You should look into what's causing the fuel economy loss. Even driving my crx like a nut, I still get around 24/25 mpg, so it has to be something engine related, not driver related. Clogged cat, bad 02 sensors, bad plugs/wires, worn distributor cap and rotor, bad/leaky fuel injectors, clogged air filter element, incorrect hose routing, all can lead to poor fuel economy.

 

Hey, 90CvcDX, I was wondering if you were able to get any pictures of your friends b18a? I took a long trip this weekend in my crx and ended up getting about 20-22 mpg on the interstate, which is better than I though I would, still pretty sure I have my hoses messed up though.

 

sorry... between work, the woman, and him working long hours i completely forgot but i will stop by his house today (july 4th) and ask him for a few shots.

 

gas mileage is pretty much the only reason to drive a STOCK civic. i used to get 42 MPG highway on my 95 LX, then a bought an si tranny and did a mini me and it dropped to about 35. then 10psi of boost dropped me to about 25 MPG.

 

After a lot of messing around with it and all the help I got on here I was able to greatly improve my mileage. After I did a tune up, that didn't seem to help much, so then I got a new O2 sensor and put that in. Then I was still getting a CEL and a 43 code. Finally I messed with the vacuum hoses until I got them right, and everything runs great now. The car now Idles at 700 rpm instead of the 1500-2000 it was doing before. For city driving I am getting about 26-29 mpg, and on the highway I have been getting an amazing 35+ mpg. This last fill up I have gotten the best mileage yet, I swear I think I may get over 40mpg. All in all I am very pleased with the increase, and I won't complain about 25+ in the city for a b18a engine.

 

Average MPG for my D15B7 ('95 Civic): 39.5