Check engine light stays on.

Replace the catalitic converter.

1 you need to get the code. 2 sounds like the catalitic converter is bad. If the code was for the exhaust sensor, the catalitic converter will pop this code.

Relaced all that and didn't check the catalitic converter. When you get codes for MAF sensor and 02 Sensors, the first place to check is vacuum leaks, if none are found then it would go right to the catalitic converter. You might want to consider another mechanic.

Here are two of the most common causes of the check engine light.

Most common, MAF ( mass air flow ), sensor. A faulty MAF prevents the computer from determining the correct fuel/air mix ratio.

Oxygen sensor. ( front and rear, front meaning before the catalytic converter, rear meaning after the catalitic converter. The front measures the fuel/air mix being sent through the catalitic converter, the back measures the emmisions and lets the computer know if any fuel/air mix ratios need to be adjusted. Both of these can trigger the check engine light.

I hope this helps you.

does this truck have gas or diesel engine?if diesel it does not have a catalitic converter
check back towards engine on exhaust to find )@ sensor

You have one on each manifold pre catalitc converter then you have one after catalitic converter sometime the use as many as four one before the catalitic converter and one after this controls fuel trim and tells the computer if the catalitc conveter is working or not. If it has two one before and one after the catalitic converter this is usedd to control overall long fuel trim. the two on each manifold will be heated so the engine will reach closed loop quickly once in close loop this allows for the rest of the engine componets to work, and that includes knock sensor timing advance and ****** and fuel rail pressure more or less depending on readingsform 02 sensors also controls when the egr VALVE comes on, if it comes on too quickly it will cause the engine to get poor fuel mileage and casue spitting out of black smoke from being to rich. Also could plug the catalitic converter and could damage the engine. Thanks for using fix-ya and hope this helps.

Not just a faulty catalytic converter will trigger this code. Many other issues can trigger this code.

• Leaded fuel was used where unleaded was called for
• An oxygen sensor is not reading (functioning) properly
• The engine coolant temperature sensor is not working properly
• Damaged or leaking exhaust manifold / catalytic converter / exhaust pipe
• Delayed spark timing
• The oxygen sensors in front and behind the converter are reporting too similar of readings

Possible solutions:

• Check for exhaust leaks at the manifold, pipes, catalytic converter.
• Replace Coolant Temperature Sensor
  
• Use a scope to diagnose the oxygen sensor operation (Tip: The oxygen sensor in front of the catalytic converter normally has a fluctuating waveform. The waveform of the sensor behind the converter should be more steady).
• Inspect the downstream heated oxygen sensor (HO2)
• Replace the catalytic converter
• Have timing adjusted
  

The catalitic converter is a mechanical device , it simply converts harmful emissions into water/vapour. The 02 sensor if faulty would put the engine management light on. If the 02 sensor has been faulty for sometime it could tell the ECU to supply the wrong amount of fuel to the engine which in turn would eventually damage the catalitic convertor. So you may have to change both in the end, but first I would check out the 02 sensor and replace if required.

Code P0132 is O2 sensor voltage high bank1 sensor 1, P0137 is O2 sensor voltage low bank 1 sensor 2, P1189 indicates a fuel control problem bank 1. It could be either the O2 sensors or a convertor. Could also be intake manifold gaskets. GM had a lot of problems with the lower intake gaskets leaking on the 3.1 and 3.4 engines that was linked to their Dexcool coolant. In fact they just lost a class action lawsuit about it. check with the dealer and see if the intake problem has been taken care of. Hope this helps.

ok the bank 1 is where the cilinder one is get a firing order and see where is the number one cylinder that's the bank one
then follow the exaust and replace the sensor after the catalitic
or converter