It will cause a problem because the ECU will be trying to go into closed loop with the O2 sensor below its operating temperature. Can you not add the wire back in?
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1984 Suzuki SJ413K pick up, 1.6 16V Baleno engine 2000 Suzuki Vitara 1.6 8V, many mods 2004 Suzuki Ignis 1.5VVT 4Grip 2006 Suzuki Jimny 1.3VVT JLX+ and many more.
I'm currently installing a g13bb into my Sierra. I've stupidly removed the heated O2 sensor wiring (orange from ecu) and was wondering if this is going to cause any issues?