02 Sensor low voltage error
#1
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
I have an 98 LS1 in my hot rod, no catalytic converters, and running only one 02 sensor on each header. The engine is running rough and the error code is low voltage on both 02 sensors.
Can someone tell me what is wrong? Thanks. I find it hard to believe both 02 sensors have gone bad. Could it be something else. How can I find out?
Can someone tell me what is wrong? Thanks. I find it hard to believe both 02 sensors have gone bad. Could it be something else. How can I find out?
#2
Moderator
iTrader: (11)
Join Date: Mar 2002
Location: East Central Florida
Posts: 12,604
Likes: 0
Received 6 Likes
on
6 Posts
![](https://ls1tech.com/forums/images/ranks/ls1tech20year.png)
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
Read the voltage with a DMM and see if you have
any sign of activity. Read heater power too. The
heater ought to have 12V wire-wire (may use a
couple of sewing needles to probe into the conn.)
and the O2 ought to be bouncing. But a gross
and untrimmed lean error could produce a stuck-
low output as would too-cold sensor (heater fault
or just the long tubes).
any sign of activity. Read heater power too. The
heater ought to have 12V wire-wire (may use a
couple of sewing needles to probe into the conn.)
and the O2 ought to be bouncing. But a gross
and untrimmed lean error could produce a stuck-
low output as would too-cold sensor (heater fault
or just the long tubes).
#3
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
I don't understand everything you said, but I assume you are saying how to test the 02 sensor? the code reader reader is saying low voltage error on both 02 sensors. Could something else be causing this? I is running bad, cutting out, erratic, stumbling.
#4
TECH Addict
iTrader: (4)
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
I don't recall if my scanner will show heater voltage, I think it just shows if the heater "passes" diagnostics.
This stuff is tough to trouble shoot, especially over the internet. Jimmy knows way more about this stuff than I do, but what he's saying is a much more succinct version of what I wrote you in a PM just now.
BTW, don't forget to check your grounds on the back of the head!
If you can't find the problem, it might be time to give a new set of sensors a shot....
![Icon Confused](https://ls1tech.com/forums/images/smilies2/icon_confused.gif)