Chevrolet Repair Questions? Ask a Mechanic for Answers ASAP
Hello, the 141 code is due to a problem with the heating circuit of the upstream oxygen sensor. This will casue the 140 code to set as well as a lean condition which can result in the surging you are having.
Does your scan tool have live data capibility? Do you have a volt/ohm meter handy to check the heater element of the oxygen sensor?
I'm going to post the test for 141 and replacement procedure below. Before you go to deep into it unplug the oxygen sensor and set your meter to ohms and check the cavity that the pink and black wire went to. If it reads open of course it's bad also check each of those wires to ground to see if it's shorted. I'll add the wiring diagram below as well.
Let me know what you find and we can work further if needed.