On the back of the block under the #4 cylinder intake runner right above the starter there is a 10mm bolt screwed into the block. Under that bolt are 4 wires, 2 brown and 2 black with white tracer. These are the grounds for the O2 sensors and the PCM O2 sensor circuitry. Remove the bolt and clean both ring terminals and the block mating area. Clean block and ring terminals with CRC Electronics Component cleaner and reassemble. You can reach these from above.
Tuesday, February 28th, 2012 AT 12:23 AM