View Full Version : O2 sensor.


BadxLS1
06-01-2012, 11:19 PM
Blew one motor in my car, put another in with a big cam and now it needs a tune, put it on the scanner and throws a o2 code. While monitoring the engine idle while still on the scanner, it reads one side running really lean and the other really rich. Plan on buying another o2 sensor tomorrow morning. Anybody else have this problem or have any suggestions. Would be greatly appreciated.

Thanks,
Mark

gnx
06-02-2012, 07:33 AM
well what does the code say. normally it will say lean bank one or lean back 2 etc..... you need to pull a vac line to see if the o2 sensors react and then you can add propane to the system to see if the o2 sensors go the other way before you replace them. just because it throws a code doesnt mean it is bad. thats what the o2 sesors are there for to tell you if it is running either rich or lean. the cam can becausing it depening on how big you went also good luck

TransamGCS
06-02-2012, 08:11 AM
like gnx said the o2 sensor is there to tell you something is wrong i wouldnt buy a o2 sensor just yet if you dont have cats you need to get the rear o2 sensors tuned out, you need to get a dyno tune by a good tuner with experience with ls engines, the tuner should be able to get every thing right, you can also get a mail order tune as well but it should just be a temporary thing until you can get the car to a good tuner

BOBS99SS
06-02-2012, 10:37 AM
I have a ms4 and dealt with the same issues, tuner got everything right though

BadxLS1
06-02-2012, 12:01 PM
well what does the code say. normally it will say lean bank one or lean back 2 etc..... you need to pull a vac line to see if the o2 sensors react and then you can add propane to the system to see if the o2 sensors go the other way before you replace them. just because it throws a code doesnt mean it is bad. thats what the o2 sesors are there for to tell you if it is running either rich or lean. the cam can becausing it depening on how big you went also good luck


Sorry for not getting a little more detailed, it's showing lean bank one.
I'm not to sure if it's okay to drive it like that, what would you say?

BadxLS1
06-02-2012, 01:37 PM
An update: swapped o2 sensors and it read the same on the other side. Bought a new one and now it runs damn near perfect.