Exhaust leak = bad gas mileage? - Honda-Tech

Go Back   > >
Log In 


Exhaust leak = bad gas mileage?

Reply
 
 
 
LinkBack Thread Tools Search this Thread
Old 11-12-2003, 09:02 AM   #1
Thread Starter
 
lilcaliplayany's Avatar
 
Join Date: Jan 2003
Location: NY, NY
Posts: 109
iTrader Rating: (0)
Default Exhaust leak = bad gas mileage?

My gas mileage is horrible. I have 150K on my teg, and have never had a prob w/ the mileage b4. I am buring a bit of oil right now, but all of a sudden i have a hole in my exhaust right by the resinator, and my gas mileage has gone down tremendously. Im fixing the exhaust prob this week, but just wondering if anyone has experienced this, or if its something else i should be looking into rather than the exhaust. thanks for the help
lilcaliplayany is offline   Reply With Quote
Old 11-12-2003, 09:30 AM   #2
 
dip-set's Avatar
 
Join Date: Sep 2002
Location: i run, N.J.
Posts: 2,086
iTrader Rating: (0)
Default Re: Exhaust leak = bad gas mileage? (lilcaliplayany)

an exhaust leak will cause your gas mileage to drop...
dip-set is offline   Reply With Quote
Old 11-12-2003, 09:34 AM   #3
Honda-Tech Member
 
roadrunner's Avatar
 
Join Date: Aug 2002
Location: CA
Posts: 401
iTrader Rating: (0)
Default

Exhaust leaks at that point in the system usually don't cause fuel economy to go down, but you may have other problems due to the high mileage. Possible items can be clogged catalyst, bad oxygen sensor, valves need adjusting, and vacuum leaks.

The oil consumption, however, would be a better indicator of the condition of your engine's internals. Have you done a compression check?
roadrunner is offline   Reply With Quote
Old 11-12-2003, 09:40 AM   #4
 
IntEGNYC's Avatar
 
Join Date: Oct 2002
Location: New York, NY, USA
Posts: 8,136
iTrader Rating: (0)
Default Re: (roadrunner)

better get a tune up. fuel economy shouldnt drop with an exhaust leak alone. The O2's may be on the way out.
IntEGNYC is offline   Reply With Quote
Old 11-12-2003, 10:01 AM   #5
Thread Starter
 
lilcaliplayany's Avatar
 
Join Date: Jan 2003
Location: NY, NY
Posts: 109
iTrader Rating: (0)
Default Re: (IntEGNYC)

Just recently did a tuneup- like w/in 4 months did my plugs/wires/cap/pcv...etc
Never any prob w/ mileage since then until now, I had the car since march w/ like 140K on it and never started buring oil untill 3 months ago when i was only drainning like seriously a quart out after 3k i started to use castrol high mileage oil, and noticed a slight decrease in my consumption of oil. Have not done a compression test yet, but figured that would be my next step. I am replacing the whole exhaust casue its a rusty piece of sh*t right now, so there may even be smaller leaks in it farther up...can i rent the compression test kit?
lilcaliplayany is offline   Reply With Quote
Old 11-12-2003, 10:13 AM   #6
Member
 
J337_UNIT's Avatar
 
Join Date: Apr 2003
Location: ???????
Posts: 1,888
iTrader Rating: (0)
Default Re: Exhaust leak = bad gas mileage? (teg-your-it)

Quote:
Originally Posted by teg-your-it
an exhaust leak will cause your gas mileage to drop...
well, it depends where the leak is. If its before the O2 sensors it could drop your gas milage..if its anywhere after the O2 sensors i dont think it really could effect gas consumption.
J337_UNIT is offline   Reply With Quote
Old 05-03-2016, 07:56 PM   #7
Honda-Tech Member
 
Join Date: Dec 2015
Posts: 4
iTrader Rating: (0)
Default Re: Exhaust leak = bad gas mileage?

I can share my exhaust leak experience on a 22 yr old Honda Prelude 2.3L. The piping rust through near the muffler, with the muffler completed felt down. I am driving without muffler for 2 days.

I filled up the gas tank, so that I can calculate the exact impact to mpg. This is an experiment I would like to find out how mpg is without muffler. During that time, I was testing ~ 700km/440miles highway, because I was visiting a friend living several hours away.

The highway mpg dropped from 29.5 mpg to 25.5 mpg, which is 13.5% poorer.

After welded the rusted pipe back with a union join, the hwy mpg resume to 29.5 mpg immediately

Fact proven that the combustion engine + catalytic converter requires certain amount of back pressure to work optimum. My best guess is O2 sensor is detecting different values, and causing the ECU mapping to the wrong efficient operating settings, e.g. intake/exhaust valve open too soon/late. In other word, it needs to reprogram the chip in order to tap on free flow exhaust, else mpg will drop
feels is offline   Reply With Quote
Old 05-03-2016, 11:38 PM   #8
Honda-Tech Member
 
JDMswagSerf's Avatar
 
Join Date: Nov 2011
Location: High Desert, CA. Age: 22
Posts: 826
iTrader Rating: (0)
Default Re: Exhaust leak = bad gas mileage? (teg-your-it)

Quote:
Originally Posted by J337_UNIT View Post
Quote:
Originally Posted by teg-your-it
an exhaust leak will cause your gas mileage to drop...
well, it depends where the leak is. If its before the O2 sensors it could drop your gas milage..if its anywhere after the O2 sensors i dont think it really could effect gas consumption.
JDMswagSerf is offline   Reply With Quote
 
 
Reply

Related Topics
Thread Thread Starter Forum Replies Last Post
Exhaust leak questions RodWolf19 Honda Civic / Del Sol (1992 - 2000) 3 06-17-2015 08:10 AM
EM1 Gas Mileage? Another_Si_Guy Honda Civic / Del Sol (1992 - 2000) 25 03-10-2015 11:15 AM
Gas Mileage? what you got widewhite Forced Induction 25 12-27-2014 01:29 PM
sudden dip in gas mileage HonestMechanic Honda Accord & Crosstour (2003 - Current) 2 08-31-2010 07:07 PM
FT: JDM ITR tranny 4:40 want to trade for gsr hydro plus cash (no grinds whatsoever). juggernaut For Sale 26 04-24-2004 12:19 PM


Tags
acura, bad, compsumtion, economy, exhaust, fuel, gas, gass, h22a, hole, integra, leak, leaking, leaks, mileage

Thread Tools Search this Thread
Search this Thread:

Advanced Search

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 On
Pingbacks are On
Refbacks are On



All times are GMT -8. The time now is 12:22 PM.



Honda and the Honda marquee are registered trademarks of the American Honda Motor Company, Inc. Neither American Honda Motor Company nor its subsidiaries or affiliates shall bear any responsibility for Honda-Tech.com content, comments, or advertising. Honda-Tech.com is not affiliated with American Honda Motor Company in any way. American Honda Motor Company does not sponsor, support, or endorse Honda-Tech.com in any way. Copyright/trademark/sales mark infringements are not intended or implied.