Exahust leak / old 02 sensor = bad mpg - Ranger-Forums - The Ultimate Ford Ranger Resource

General Ford Ranger Discussion General discussion of the Ford Ranger that does not fit in any other sub-forum.

Exahust leak / old 02 sensor = bad mpg

Reply

 
 
 
  #1  
Old 01-06-2009
wydopnthrtl's Avatar
Member
Thread Starter
iTrader: (2)
Join Date: Dec 2005
Location: Ohio
Posts: 2,454
Exahust leak / old 02 sensor = bad mpg

Guys, I've been doing a lot of reading on some tuning forums.

One thing I see over and over again is that exhaust leaks cause inaccurate 02 readings. Even very small leaks! The result is often excess fuel consumption and one bank running richer than the other.

So.. if you feel your mpg is down as compaired to where "it used to be"? A thing to check is for exhaust leaks. **especially** at the header to mid-pipe connection. Leaks back by the muffler can effect it.. but not much.

Also, 02 sensors that have more than 60k miles on them will start to get "lazy". Meaning that they work. But they swing from high to low and start to falsly read leaner and leaner which adds fuel.
 
Reply With Quote
  #2  
Old 01-06-2009
Join Date: Apr 2006
Location: Ganado, TX
Posts: 356
True!

The "Donut" gasket was leaking on my truck (the gasket before the cat).
My mileage was no good, even though the leak was very small. I repaired that leak, replaced the upstream sensor, and the mileage improved.

It also fixed a intermittent CEL.
(On of those CEL's that drive you nuts because it's so vague!)
 
Reply With Quote
  #3  
Old 01-06-2009
Goodysgotacuda's Avatar
Member
iTrader: (1)
Join Date: Jul 2008
Location: Las Vegas, NV
Posts: 1,496
Any exhaust leak before the sensor will cause lean readings and richer mixtures
 
Reply With Quote
 
 
 
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
NP94B2300
SOHC - 2.3L & 2.5L Lima Engines
2
01-25-2014 11:51 AM
one1
Vehicle & Meet Videos
15
12-27-2011 06:00 PM
MonsterGuy
General Technical & Electrical
11
08-06-2007 04:29 PM
rideabikenick
Exterior Semi-Tech
37
02-09-2007 09:35 AM
FMD
General Ford Ranger Discussion
13
04-25-2006 08:21 AM


Thread Tools
Search this Thread
Quick Reply: Exahust leak / old 02 sensor = bad mpg


Contact Us Sitemap Advertising Cookie Policy Privacy Statement Terms of Service

We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.