pruney81

Well, i got a code 25 a few weeks ago so I replaced my o2 sensor because I had been getting 13.5 mpg around town. I've got 160k miles on my truck so I thought a new o2 would help mileage. It didn't do anything at all that I can tell. What else could a code 25 be? The check engine light only came on once and it came up with a code 25, I then disconnected the battery and it went away. What else could a code 25 be? Would a tired EGR valve affect gas mileage?

thook

Code 25:

AIR/FUEL RATIO LEAN INDICATOR--LEAN SIGNAL SENT TO ECU FROM O2 SENSOR
--INJECTOR FAULT(S)

--FUEL PRESSURE

--OXYGEN SENSOR

--AIRFLOW METER OR MAP SENSOR

--IGNITION

--ECU


Happy hunting...

pruney81

Ahhh..you said it.

thook

hehehe....

gonzo

Don't you have 2 02 sensors? Mine does

pruney81

I only have one right before the cat as far as I can tell. Is yours a CA vehicle by chance?

gonzo

not that I know of. I have 1 before the cat and 1 before the muffler

pruney81

Mine was built in 9/95 and it only has one o2 sensor. I know the CA models had 2 o2 sensors.

gonzo

I do know the the original owner. It was bought in NH.
All I know, but it does have 2.

Knuckles

you what!

sorry for the immature comment. i just found it funny.

gonzo

LMAO
OPPS
I "know"
LMAO
There, fixed. lol

thook

It was more interesting the other way...lol

Jason Holdeman

Mine is also only giving a code 25....
And i am getting horriable fuel millage....
I have replaced my fuel injectors with a set from flamethrower, replaced my fuel filter, replaced my afm ( p.o. was inside it and dinnt make anything, was getting a 25 and 26 code till i did that)
Egr valve and pair valve delete so i can see the #5 plug now!!!
And the idle is sub par.....
I do not understand what is going on here im only getting a code 25 but like 7 miles to the gallon!!!!!
The only thing i have not checked is my fuel pressure, ignition, ecu, aand o2 sensor....
She only has 127k on her and has had a new heads put on in 05 at 105k....