When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
Okay.. first I have to say I am new to this so if I breach some rule or this has been beat to death I apologize up front. I have a 1987 V1500 305 TBI. The oil pressure guage will not work. I have read multiple threads that contradict each other about which or the 2 sensors makes the inside guage read pressure. Can someone please confirm. I have changed out the sensor by the oil filter. It has one orange wire going to the male flat connector. It also happens to have a light brownish wire coming out of the same harness beside it that connects to nothing, should that be connected to something such as a different type sensor or can anyone tell me where that should be located?
This is the plug that is hanging
Top picture is what I replaced and the second photo is the hanging end of the brownish wire. Any help would be greatly appreciated.
The gauge is ran off of the sensor in your pic, and the tan wire is for the fuel pump operation. If the ecu doesn't see oil pressure it won't allow the fuel pump to run. This is so if you wreck the car and the engine dies the pump wont keep supplying fuel.
I think I got my wires wrong... Does the tan wire also have a flat connector on It? If so that might be the wire for the gauge and 5he other wire is for the ecu.
OK, the dash gauge is run by the sensor you show in the first post. It was likely mounted on a 90* fitting that is threaded into an oil passage above the oil filter.
The other wire/connector may be a faded purple in color. It is likely for the O2 sensor.
About the oil pressure switch by the distributor. It is a backup to the fuel pump relay. It will not prevent the fuel pump from running if there is no oil pressure.
It is a back up in case the fuel pump relay or the driver for the relay in the ECM fails.
1. As said, the sending unit by the oil filter drives the dash gauge.
2. That sending unit has a long, sad history of premature failure.
3. When it fails, the gauge may read high, low, or wildly variable.
4. There is a zero percent chance you'll find a replacement sensor that's made in America.
5. When you remove the sensor, there's a fair chance it will be half-full of oil.
6. Replacement sensors may be the same size as original, or somewhat larger. The larger ones are difficult/impossible to install in my K1500.
7. Be sure the sending unit you buy matches the dash gauge. Seems to me there's a 60-psi sending unit to match my K1500's 60-psi gauge, but there's also a 40 or an 80 psi sending unit that looks the same from the outside.
06-29-2017, 11:20 AM
