knock sensor
Code 23 in your 1993 Chevy Blazer is referring to the Manifold Air temp sensor being out of range. Start by looking for the sensor to see if it is unplugged.
Trouble code P0135 means:O2 sensor heater circuit malfunction (Bank 1 Sensor 1)
Trouble code P0325 means:Knock sensor 1 circuit malfunction
ESC / Electronic Spark Controll Circuit. and the knock sensor signal.
Trouble code P0144 means:O2 sensor circuit high voltage(Bank 1 Sensor 3)
Trouble code P0186 means: Fuel Temperature Sensor B Circuit Range/Performance
What this trouble code means that the input power(+) to the speed sensor is low.
it could be your fuel regulator .it wont set a code on this if it is going out
I have a code DTC P0154.Bank 2 Sensor 1 no activity.Which sensor is this on my 96 Blazer?
knock sensor
If it had a bad O2 sensor the "check engine" would be illuminated and a code would be set indicating which sensor is at fault. You probably have other problems causing that backfire to occur.