Already changed both o2 sensor - 2005 Chevrolet Equinox

P1151 is indicating an problem with the upstream O2 Sensor on Bank 2. Bank 2 is the even cylinders side O2 sensor. The P0175 code indicates a rich condition in Bank 2 exhaust. This indication, if by itself, would indicate a faulty MAF Sensor or a vacuum leak, but since you already have the P1151, change the Bank 2 O2 sensor first and most likely both codes will clear.

The car has more than one O2 sensor. This code is for Bank 1 sensor 1, on the exhaust manifold.

pull o2 senser and clean if stops, check items that makes it run rich. timing, vaccum lines and list goes on

The engine may have a intake vacuum leak. A defective O2 sensor has no effect on engine idle or performance.

Do you only have one o2 sensor? Many cars have two- one in front of catalyst, one behind. The front one is for fuel trim.
Also, that code is for the whole o2 circuit, right? Might need to keep checking. Does your car have a heated o2 sensor? Just another circuit to check, if so. good luck.
Looked at your post again. See where you said o2 sensors. Already changed both, huh? Wow. good luck. Might need a multimeter for resistance test of circuits.

P1151 means a lean bank 2 O2 sensor
P1152 Means a rich bank 2 O2 sensor
P1309 Means miss fire detected
I would check your fuel injector for fouling
When they foul the will develop a drip
Causing a fuel fluctuation that will have O2 sensors reporting rich and lean voltage changes
This causes the pcm to adjust injector pulses making them shorter and longer.
causing more fuel or less fuel.
From this condition you may see plug fouling.
Also check for leaking or faulty fuel pressure regulator or restricted return line.
Most of the time it wont be a bad O2 sensor the O2 sensor is just doing its job.
You also have already changed the plugs and Map so there already out of the way.
If this helps please give me some feed back
Hope this works for you FixYa

Given that most of the trouble codes are for the O2 sensor, I think I would change it. The multiple misfires could be because of improper fuel/air mixture caused by a bad sensor. Disconnect the negative(-) battery terminal then change the sensor. Disconnecting the negative(-) should reset the computer and allow the fuel/air mixture to return to default allowing the engine to start.
P0130 - O2 Sensor Circuit Malfunction (Bank 1 Sensor 1)
P0134 - O2 Sensor Circuit No Activity Detected (Bank 1 Sensor 1)
P0135 - O2 Sensor Heater Circuit Malfunction (Bank 1 Sensor 1)
P0141 - O2 Sensor Heater Circuit Malfunction (Bank 1 Sensor 2)
P0300 - Random/Multiple Cylinder Misfire Detected

17584/P1176/004470 - Bank1: O2 (Lambda) Correction Behind Catalyst: Control Limit Reached Possible Causes

• Intake Air System leaking
• Oxygen Sensor(s) and/or Oxygen Sensor Control faulty

Possible Solutions

• Check Intake Air System for Leaks (False Air)
• Check Oxygen Sensor(s) and/or Oxygen Sensor Control (all of them!)

This is the pre 02 sensor located before the catalytic converter.

At the autoparts store they sell special tools to remove O2 sensor. (around $ 20) Make sure you put anti-sieze on threads before install and don't overtighten (You may have to take it off someday)
I guess you already have a good reason why you are replacing O2 sensor? And yes doing yourself is worth it.
Tip: cold exhaust parts sometimes won't come apart, Warm parts come apart better but you have to be careful not to get burned!
Warm not Hot!

ox. sensor no. 1 check exhaust pipe below exhast manifold