Service Engine Soon Warning Light
Burning Brakes
Joined: Nov 2005
Posts: 848
Likes: 1
From: 1992 LT1 6 speed Cayman Islands
If you are getting codes 13 and 64 again you do not need to replace your O2 sensors again. Ther are doing the job they were ment to do and are reporting a condition. You need to fix the cause of then throwing the code.
You say that the mechanic said that the O2 sensors were reading low & not exceeding 600mV.
A. On a code 13 less than 300mV indicates one of three things:
1. Open circuit 412. - This is the purple wire that goes fron the ECM connection pin A16, to the O2 sensor. Check along this wire where it pigtails into this wire and make sure the connection is clean. Make sure this wire is not burnt against the exhaust
2. Faulty ECM connection. - Pull off ECM connections and clean with an electronics spray.
3. Bad ECM
B. On the same code 13, if the voltage at the O2 sensor is between 300mV and 600mV it is definately a bad ECM and nothing else
C. on a code 13 more than 600mV indicate
1. Open to ECM ground.
2. Faulty connection to ECM
3. Faulty ECM
It seems that the mechanic may be right and you will have to buy a new ECM after you have eliminated the other two possibilities depending on what the reported voltage is.
Ask the mechanic exactly what the voltage reading was when it threw the code 13 and if it is between 300mV and 600mV the only possibility is a new ECM
Hope this helps.
Jerris
You say that the mechanic said that the O2 sensors were reading low & not exceeding 600mV.
A. On a code 13 less than 300mV indicates one of three things:
1. Open circuit 412. - This is the purple wire that goes fron the ECM connection pin A16, to the O2 sensor. Check along this wire where it pigtails into this wire and make sure the connection is clean. Make sure this wire is not burnt against the exhaust
2. Faulty ECM connection. - Pull off ECM connections and clean with an electronics spray.
3. Bad ECM
B. On the same code 13, if the voltage at the O2 sensor is between 300mV and 600mV it is definately a bad ECM and nothing else
C. on a code 13 more than 600mV indicate
1. Open to ECM ground.
2. Faulty connection to ECM
3. Faulty ECM
It seems that the mechanic may be right and you will have to buy a new ECM after you have eliminated the other two possibilities depending on what the reported voltage is.
Ask the mechanic exactly what the voltage reading was when it threw the code 13 and if it is between 300mV and 600mV the only possibility is a new ECM
Hope this helps.
Jerris
