I had to relocate the oil pressure sending unit from the top-back of the block to the oil galley on the driver side of the block behind the power steering pump for my KB install and now my oil pressure guage is pegged like the connector is unplugged. If I damaged the guage when I installed it would it read like and open circuit or is it more likely that wiring is messed up? Anyone know what kind of signal the one pin/wire sending units put out to the pcm so I can check it? I already took a mirror and looked for a bent pin on the sensor but it looked fine.

 

The sending unit is a variable resistor. The circuit reads the resistance and translates it into oil pressure readings.

You can check the wiring by disconnecting the sending unit wire, and checking the oil pressure reading. Then take a paper clip and short the sending unit plug to ground (if it is a two wire plug, short the two wires with the paper clip). When the circuit is open (disconnected) the oil pressure gauge will peg one way (I believe it is zero). When shorted, the gauge should peg the other way. If you can peg the gauge in both directions, then the problem is in the sending unit.

 

Thanks, I will try that. If it is a variable resistor, I presume it is grounded thru the threads of the sensor? I believe the elbow KB send to connect the sensor to the block is plastic or composet. That could be an issue. :hmm: If the paper clip trick works, I may try jumping the body of the sensor to the block to see if it reads anything.

 

Yes, a single wire system is grounded through the threads. A 2-wire system is grounded through the second wire.

 

Evidently I put too much teflon tape on the threads (as per KB's instructions) which isolated the sensor ground. I put a jumper on it for a temp fix till I can do a permanent fix this weekend.

 

So did the jumper fix it?