The problem is I am getting about 18mpg with the H22. I have replaced all the ignition components including a new distributor (unrelated issue), new fuel filter, and new oxygen sensor. Any other ideas as to what I can do to imporove this crappy gas milage? Also all the parts that are new were done because of the engine swap not for troublshooting reasons.

 

That's not *that* bad. AFAIK, the H22 only gets about 22mpg on average. I struggle to keep it above 20mpg, but I have a heavy foot.

Hows tire pressure? Air filter changed/cleaned? How's your driving habits? Lots of highway, mostly city? Lead foot (like me)?

 

I get on average 21 mpg.

I'd also change the air filter, about to change mine, I'll check for much a difference.

How often do you hit high revs? I have a lead foot also, but when I can keep myself below 4grand, I get better mileage.

 

Most of the time I never go above 4000 and usually cruise around 2500 - 3500. The lead foot isn't a problem and the air filter was cleaned recently. I also do about 50/50 highway and city driving. I figured the mpg should have been better after reading about some guys on here getting around 24+ mpg. Maybe I am just on the other side of the scale for average.

 

I just noticed your profile that you're running a P28 ECU. I know nothing about ECU's, but I guess it could be something to do with your A/F ratio being too rich. Are you chipped/tuned? Hopefully someone with more knowledge can help you, I'm just throwing out suggestions.

 

I've never paid attention to my mileage in my Prelude, but I get 24mpg average in my MR2....I sure hope to hell that I'll get better than that in my Honda!

 

I usually get about 24 mile per gallon. My old H22 got like 29!

 

wow these are terrible #'s
when i first got my car i was getting 25...added a k&n drop and saw as high as 27
never been below 23 or 24 and i don't think my car sees a day without vtec

maybe i am lean

 

Have you checked your tire pressure?

 

Sorry for the slow response I have been away from the computer a bit. My ecu is chipped/tuned, tire pressure is perfect, and I have a manual. I think that I am going to try and take my car in to get it retunned, this gas milage just isn't cutting it.

 

It might be the chip you have.

 

I was thinking the chip also but the tuner only made a few adjustments according to my mods. I think that I am just going to go in and have it retuned on the dyno once I get my tax return.

 

Yeah it is probably the chip.. When I ran hondata I got like 20mpg barely and with the jdm p13 I usually get 26+ mpg.... so that sounds like it....

 

woah if i drive like a pansy and shift at 3000 rpm +200/-200 rpm and dont break hard i get 18 mpg... my tires are all at 32 psi and i check them like every other day. I just got a tune up like 1000 miles ago and all my fluids, spark plugs, and even my air filter were replaced. I think i might have to get a new o2 sensor. I got a cell last week but just got my ecu resetted. CEL code i got was 172. Said i was running to rich. I've been driving for a while and i havent got the code back yet. I'm thinking about changing my o2 sensors but I've heard that preludes are very picky on o2 sensors...$255 for a new o2 sensor from Honda is really expensive... Oh yea, and my car is completely stock.... nothing to weigh the car down but a bottle of oil in my trunk..

 

something is wrong cause I run the crap out of my car -- it has a jdm h22a in it and I run 93 octane gas, have dynoed the car at close to 200 whp and still get 26-28 miles to the gallon on a fill up... check your CEL and fix the problem....

 

well i do only do city driving....only drove highway once.. i even use shell 91
V-power maybe i should use some fuel injector cleaner for now? Any recommended brands? Was about to buy a 6 dollar bottle of stp complete Fuel system cleaner at Walmart. Well i was between fuel injector cleaner and complete fuel system cleaner.. but didnt buy any becuase couldnt make up my mind lol and didnt know which could provide better results for mpg..

 

do not know have never done much looking into fuel injector cleaners. Though I think stp or gunk would work well. Yes that is true city driving does make a difference most of my driving is interstate.....

 

A good alignment might do the job, and like other people said clean the fuel injectors/throttle body, and leave the rims stock or get lighter ones with same diameter for better mileage.

 

Buy a civic hybred, if you cant afford Da gas...Or just take the Bus