Diagnostic Trouble Code P0137

My SL1 Failed Emissions Test because Service Engine Soon light was on. The Diagnostic Trouble Code Reported was P0137 O2 sensor circuit voltage low.

Repair facility is telling me that "the catalytic converter is coming apart which has caused the O2 sensor to go bad."

They have quoted $777 plus tax to replace both the catalytic converter and the O2 sensor.

Does this make sense?

P0137 - Heated O2 sensor (rear) low voltage

although the cat could be bad, more likely it is just the sensor, or the wiring to it. if you had a bad cat YOU WOULD KNOW IT. your car would have NO power, you would be lucky if you could go above 35 MPH, and hills? forget it. what year is it? i beleave the factory cats have a 8-year warrenty, mandated by law, i don't know how old that law is though. really the cat shouldn't go bad unless some other problem caused it. ever have your ECT replaced?

my advise, replace the sensor, check the wiring, and if that doesn't work then replace the cat.

It is a 1997 SL1. As far as I know the ETC has not been replaced. I have owned the car for three years. What exactly is an ETC?

engine coolent temp sensor, the first design failed massively after a few years. it was redesign around 2001, the new design should last for ever. when the ECT fails the computer will think the engine is to cold, so it will spray more fuel into the combustion chamber. results in higher idle/rough idle, hard starts, poor MPG, missreading dash gauge, and in a some handful of cases, if the ECT has been bad for a very long period of time the extra fuel shortens the cat life. this is not very common. my cat lived 9 years with the old ECT design, but there were a few other things that killed it. the ECT is a $15 peice, and a easy repair for the DIYer, i would recommend replacing the old design with the new one, whether is was bad or not. many times, it pays for itself in a few gas tanks.