97 Civic HX MPG not up to snuff - Fuelly Forums

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

Reply
 
Thread Tools Display Modes
 
Old 12-14-2013, 01:59 AM   #1
Registered Member
 
Join Date: Dec 2013
Posts: 1
Country: United States
97 Civic HX MPG not up to snuff

Hello the camp...new member to your forums needing some assistance.

We recently helped my daughter buy a 97 HX specifically for the fuel mileage aspects. She drives the car back and fourth to school which is about 18 miles one way most of which is highway. After driving it for several tanks at various speeds....first tank 75 ...then 70...then 65...then 60 (Which is hard to do when the speed limit is 75 on this TX Hwy...bless her heart she was a trooper to test for the sweet spot on mileage).

I have read you need to keep the RPM at or below 2500 rpm to reap the benefit of the HX's fuel economy which we have done repeatedly.

The problem is that at any of those speeds the best we have done is 33 mpg.

There is no CEL and the car runs and drives just fine. I have replaced the air filter (which was a mess) spark plugs, cap/rotor and just put new Michelin tires on it (not just for economy...it needed tires anyway) as well as an alignment and so far nothing has had an impact...still 30ish mpg.

I am going to try cleaning out the EGR valve next and check the timing as these have been suggestions.

Anybody have some insight as to why this HX is only getting 30-33 MPG with no check engine light? She is not using any fancy driving techniques but she is also not a lead foot so I really don't get it. This car I would think should be getting into the high 30's low 40's easily....
__________________

vxhbb16a is offline   Reply With Quote
Old 12-14-2013, 06:42 PM   #2
Registered Member
 
bowtieguy's Avatar
 
Join Date: Oct 2008
Posts: 1,873
Country: United States
Location: orlando, florida
First thing that comes to mind is thermostat. Could be stuck open or even missing(happened to me). Also fuel filter. Just for giggles, I'd have the car scanned for codes. Could have the CEL bulb removed(also happened to me).

Best of luck and great choice in vehicles!
__________________

bowtieguy is offline   Reply With Quote
Old 12-15-2013, 04:04 AM   #3
Registered Member
 
IndyFetch's Avatar
 
Join Date: Nov 2008
Posts: 627
Country: United States
Location: Indianapolis
Check for proper NGK plugs and good plug wires. Good idea to change the cap and rotor, too. You could have a rear brake dragging - jack up the rear end and see if the wheels turn without the e-brake on. These cars run a lot better after a valve lash adjustment. If it has not been completed anytime recently, or within the last 90K miles, replace the timing belt just to be safe. Make sure your tires are in good shape and inflate them to the sidewall max. Of course, Low Rolling Resistance (LRR) tires are best for mileage.


When I bought my VX, I was getting about 44 mpg. After a valve lash adjustment, tune-up, better tires, and rear brake adjustment, mileage soared into the low 60s.


One last thought - Honda are more affected by winter blend gas than anything else I've driven. My Accord dropped from 31-33 mpg to 27-29 mpg, with the only change being our stations' switch to winter blend. My other Hondas (VX, del Sols, '99 Si, '05 Si, '08 Si, '10 FIt) have had similar drops on winter blend gas.
IndyFetch is offline   Reply With Quote
Old 06-03-2014, 08:31 AM   #4
Registered Member
 
Join Date: May 2014
Posts: 3
Country: United States
Oh wow! I had a Civic VX hatchback a long time ago and loved it. I never calculated the MPG back then though. I do remember it would do 114MPH in 3rd gear though!
snatchell is offline   Reply With Quote
Old 06-03-2014, 08:33 AM   #5
Registered Member
 
Join Date: May 2014
Posts: 3
Country: United States
I also had a Civic HX CVT at one time. It was a black coupe. That was a cool car but I never calculated MPG on it either.
snatchell is offline   Reply With Quote
Old 12-06-2014, 01:57 PM   #6
Registered Member
 
Join Date: Aug 2014
Posts: 159
Country: United States
Location: East Teggsas
You mentioned the EGR, and that's the first place my mind goes on any lean-burn Honda (HX, VX or 1st-gen Insight). They rely heavily on, and are super-sensitive to, the EGR functioning properly. I hope you will report back here!
Jcp385 is offline   Reply With Quote
Old 02-17-2015, 07:33 AM   #7
Registered Member
 
Join Date: Aug 2014
Posts: 159
Country: United States
Location: East Teggsas
Well, another thought. Not sure if you're still seeking advice, but I'll throw it out there. US emissions regs forced Honda to really severely narrow down the conditions under which it will utilize lean-burn. It could be that the commute offers little to no opportunity for lean burn to be activated.
Jcp385 is offline   Reply With Quote
Old 02-17-2015, 08:10 AM   #8
Registered Member
 
Join Date: Nov 2014
Posts: 5
Country: United States
no stock VX can do 113mph

Quote:
Originally Posted by snatchell View Post
Oh wow! I had a Civic VX hatchback a long time ago and loved it. I never calculated the MPG back then though. I do remember it would do 114MPH in 3rd gear though!
There is no VX that can do 113mph in any gear let alone third gear.
You must have had an SI not a VX.
softciyVX is offline   Reply With Quote
Old 05-03-2015, 07:33 AM   #9
Registered Member
 
Join Date: May 2015
Posts: 3
Country: United States
I agree with the winter blend and timing belt as a possibility.
Ferrigamo is offline   Reply With Quote
Old 06-17-2015, 01:08 AM   #10
Registered Member
 
Join Date: Sep 2014
Posts: 58
Country: United States
Quote:
Originally Posted by Jcp385 View Post
You mentioned the EGR, and that's the first place my mind goes on any lean-burn Honda (HX, VX or 1st-gen Insight). They rely heavily on, and are super-sensitive to, the EGR functioning properly. I hope you will report back here!
I know lean burn will not engage unless I am at 65 mph or less under very light load with a rock steady foot on the pedal. If she is the type to slightly accelerate than decelerate a lot (which my mom, wife and sons do) then it wont go into lean burn.

When lean burn is on my mpg increases by 30 mpg.
__________________

itripper 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
Winter mix and timing northwoods2 General Fuel Topics 3 02-13-2013 06:55 AM
$100 Civic VX 5 wire O2 / LAF sensor. will it work? GasSavers_ian General Maintenance and Repair 3 12-22-2012 08:24 PM
Quest for better MPG. jbadamo Introduce Yourself - New member Welcome 3 11-28-2012 01:28 PM
Sailboat at The Golden Gate, from the VA Hospital shatto General Discussion (Off-Topic) 0 10-27-2012 09:53 AM

Powered by vBadvanced CMPS v3.2.3


All times are GMT -8. The time now is 07:51 PM.


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