Welcome Visitor! Please take a few seconds and - Joined
- Jun 2, 2012
- Messages
- 25,363
- Reaction score
- 8,367
- Points
- 113
- Location
- canada
- Vehicle Year
- 1994
- Make / Model
- Ford
- Transmission
- Manual
Good work 
In the late 1980's Ford switched from an oil pressure sender, to an oil pressure switch(on/off) that closed when pressure was above 5.5psi.
They added a resistor to the back of the oil pressure gauge so it showed between 1/4 and 1/2 on the gauge when switch was closed(grounded).
So any difference in oil pressure gauge needle would be electrical not actual oil pressure, and REVing engine increase on gauge would be alternator voltage increase.
In the late 1980's Ford switched from an oil pressure sender, to an oil pressure switch(on/off) that closed when pressure was above 5.5psi.
They added a resistor to the back of the oil pressure gauge so it showed between 1/4 and 1/2 on the gauge when switch was closed(grounded).
So any difference in oil pressure gauge needle would be electrical not actual oil pressure, and REVing engine increase on gauge would be alternator voltage increase.
