I found the oxygen sensor had been broken off on the 1995 chevy k1500 5.7L truck I recently bought. The only cut wire I can see near there is a large dark blue wire. The wiring diagram says it should be a purple one and doesn't say what gauge it is. Does anyone know of an oxygen sensor with a big blue wire attached to it?
Which trans does it have? The 4L80E equipped vehicle uses a different sensor than the 4L60E. One (4L80E) is single (purple) wire while the other is a 3 wire (purple, black, pink) On either one the signal wire is purple. The pink & black wires are for a heated O2 sensor. If the sensor was broken off the wires going up front may have been ripped out of the harness itself.
Connection A10 on the ECM is the O2 signal line. On the 3 wire the Pink is fed from fuse Eng-1 (20A) in the under hood box. The Black is a GOOD ground.
It's a manual transmission. The original engine was a 4.3l v6 but they had put in a 5.7l v8. I'm trying to get to the ECM to see if I can trace the blue wire back to that connection as all the connectors seem to be behind the brake master cylinder.
Still should have the same wiring colors. With a stick/4.3 it should have the 3 wire sensor harness. The O2 sensor is the same part for the
4.3 and 5.7 with a stick.
I got to the ecm. Haven't traced the wires yet but I got some numbers off the prom. Can't find anything on line to id it though. The number was delco
9946 bjww.
Won't matter. The 4.3, 5.7, and 7.4 all used the same ECM and PROM type. It is how that prom is flashed that creates the magic.
4.3 to 5.7 is almost a drop in anyway. You only need a few pieces for the conversion. Basically a different fan shroud and change a few hoses.If this truck was running before I would say you just need to figure out the wiring issue.
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