Hello all, I'm new here, thanks for letting me join in. My problem is as I drove home my new to me 99 Sunfire the rpms started dropping off till I tried to accelerate then it would surge forward until the rpms again topped out and started to bogg down. We stopped to check things out and found the wiring to the exhaust manifold O2 sensor was poorly connected and rubbing against what I believe is an egr pipe. We roadside fixed it with electrical tape and it started, ideled, and ran fine for 10 miles or so than started acting up again. Once home I looked over the wiring and checked out various web sources to find out there is a snap connector missing between the sensor wires and main loom. Also one of the sensor wires was not even connected to anything! My problem is to figure out were the wires should be connected to which wires since I don't have the connector. The loom wire is purple and the sensor wires are black and gray. The black sensor wire was connected to the purple loom wire. Any help would be appreciated. Also there was no heat sheilding on the sensor wires as shown in several images I found on the net. The car test drove fine and for the first 15 miles. Also the motor was swapped with a lower mileage one. Thanks for your time and patience.
99 Sunfire exhaust O2 sensor wiring?
- Thread starter m715
- Start date
Zimgxp
New member
The purple is the sensor wire. The other two are probably for the O2 sensor heater.
Yeah the manual diagram shows black from sensor connected to purple to wiring harness. There is only two wires coming from the sensor, black and grey, The diagram shows second wire going to ground but doesn't list it's color. Thanks for the input all, I'll be redoing the wires with soldered joints shrink tubing and heat tape.