94 vx only getting 25 mpg!?! - Fuelly Forums

Android Users - Coming Soon! - Migrating from aCar 4.8 to 5.0

Reply
 
Thread Tools Display Modes
 
Old 02-06-2012, 11:46 AM   #1
Registered Member
 
rsport's Avatar
 
Join Date: Feb 2012
Posts: 7
Country: United States
94 vx only getting 25 mpg!?!

ok, i am new to the site here. and i am hoping for a miracle with the guru's here.
i bought a 94 vx las october knowing that it was going to be a project. but the guy didnt disclose all the problems the car has so now i am in it further than i thought i would be.
i have fixed alot of the cosmetic and critical problems with the car. she starts right up, feels very strong, does not smoke, tranny is smooth, handles very well, and sounds great. except i am only getting 25 mpg. 90% of my driving is city stop and go, about 20 miles/ day.

things i have done so far.
new oem spark plugs, correct gap.
new fuel filter.
fresh oil and oil filter.
new air intake with new filter.
new tires, with lightweight rims.
alignment
DC sport headers, custom 2.5 inch exhaust
lowered 3 inches.
vx transmission with new clutch.
new battery

other issues:
the CEL comes on at 45 mph.
the speedo does not work right.

I just ordered the 5 wire O2 sensor for it.

I think i might need to do a timing adjustment and valve adjustment.

I would greatly appreciate any help. thanks for your time.
__________________

rsport is offline   Reply With Quote
Old 02-06-2012, 01:31 PM   #2
Registered Member
 
add|ct's Avatar
 
Join Date: Jun 2010
Posts: 534
Country: United States
Re: 94 vx only getting 25 mpg!?!

Check PSI in the tires, should be into the high 30s at least. Most on this site recommend near or at max sidewall pressure.

Which 5-wire did you order?

Replace your Vehicle Speed Sensor. Easy but somewhat pricey, depending on where you get it. Check RockAuto or Amazon.
__________________

__________________
'92 Civic VX, Canadian model
add|ct is offline   Reply With Quote
Old 02-06-2012, 02:27 PM   #3
Registered Member
 
bowtieguy's Avatar
 
Join Date: Oct 2008
Posts: 1,873
Country: United States
Location: orlando, florida
Re: 94 vx only getting 25 mpg!?!

the thermostat is often over looked. does the car get fully warmed up?
bowtieguy is offline   Reply With Quote
Old 02-06-2012, 02:35 PM   #4
Registered Member
 
rsport's Avatar
 
Join Date: Feb 2012
Posts: 7
Country: United States
Re: 94 vx only getting 25 mpg!?!

o2 sensor is the 5 wire ntk 24300.
thermostat is fine.
i will check tire pressure as soon as i can. i only have maybe 400 miles on the tires so they shouldnt be any lower than what the tire shop set em up as.
i am looking into the vss right now.
rsport is offline   Reply With Quote
Old 02-06-2012, 06:58 PM   #5
Driving on E
 
Matt Timion's Avatar
 
Join Date: Sep 2005
Posts: 3,110
Country: United States
Re: 94 vx only getting 25 mpg!?!

Your CEL is the key. get a new o2 sensor ($135 on ebay, I think). Your VX will never enter lean burn mode without a properly working o2 sensor.
Matt Timion is offline   Reply With Quote
Old 02-07-2012, 10:05 AM   #6
Registered Member
 
GasSavers_TomO's Avatar
 
Join Date: Oct 2006
Posts: 1,108
Country: United States
Send a message via AIM to GasSavers_TomO Send a message via MSN to GasSavers_TomO Send a message via Yahoo to GasSavers_TomO
Re: 94 vx only getting 25 mpg!?!

That 2.5" exhaust piping isn't going to help with City driving either...1.75" diameter would be best but 2" is usually cheaper if making your own exhaust. And 2" will be ok to use.
__________________

Honda Civic VX Info/Links
Remember to use good Webiquette!
Quote:
Originally Posted by ezeedee View Post
controversy is an idea thought up by weak people who are too afraid to hear the truth.
GasSavers_TomO is offline   Reply With Quote
Old 02-07-2012, 12:53 PM   #7
Registered Member
 
add|ct's Avatar
 
Join Date: Jun 2010
Posts: 534
Country: United States
Re: 94 vx only getting 25 mpg!?!

I'm thinking the exhaust mods may be somewhat of a culprit here as well. Let's see how the performance changes with the new 02 once the OP installs it.
__________________
'92 Civic VX, Canadian model
add|ct is offline   Reply With Quote
Old 02-07-2012, 06:45 PM   #8
Registered Member
 
rsport's Avatar
 
Join Date: Feb 2012
Posts: 7
Country: United States
Re: 94 vx only getting 25 mpg!?!

yeah, the funny thing is, i starting collecting parts for a civic course race car before i bought the car. i found the civic hatch for really cheap (cause it was in baaad shape) knowing i was going to be replacing alot of parts with performance parts anyways. i didnt realize the car was a vx until i did some more research on the car. so i still put on my performance parts but instead of doing an all out race car, i wanted a well balanced fuel efficient car for spirited driving. im not looking to get 50+ mpg but i sure as heck should be getting more than 25. i would be happy with anything more than 35.

who knows, if i cant get the engine running right, i might sell the whole VX swap to the right person, with them knowing that it needs to be rebuilt.
rsport is offline   Reply With Quote
Old 02-08-2012, 08:47 PM   #9
Driving on E
 
Matt Timion's Avatar
 
Join Date: Sep 2005
Posts: 3,110
Country: United States
Re: 94 vx only getting 25 mpg!?!

it's possible the previous owner tried to modify some stuff. Ensure your ECU is a p07. Also ensure that the EGR valve is plugged in. If it isn't, it's possible a previous owner put a different engine/transmission in there.
Matt Timion is offline   Reply With Quote
Old 02-08-2012, 10:05 PM   #10
Registered Member
 
theclencher's Avatar
 
Join Date: Aug 2006
Posts: 542
Country: United States
Re: 94 vx only getting 25 mpg!?!

Matt's alive! Where have you been?
__________________

__________________
Tempo/Topaz:
Old EPA 23/33/27
New EPA 21/30/24

F150:
New EPA12/14/17

theclencher is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Fellow Gun Nuts shatto General Discussion (Off-Topic) 2 05-09-2009 03:12 PM
online manual or specs. for suzuki 81 gs450 guest001 Motorcycles 0 07-11-2008 09:43 PM
Turbocharger Market 2010 ~ what does it mean? 44mpg by 2010 General Fuel Topics 1 03-01-2008 04:35 PM
Congratulations Jared!!! SVOboy General Discussion (Off-Topic) 7 08-13-2006 09:55 PM

Powered by vBadvanced CMPS v3.2.3


All times are GMT -8. The time now is 08:38 PM.


Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.