Fake oil pressure gauge

[jimandmandy]

When did Ford stop using a real oil pressure sending unit? I was troubleshooting the gauge and checked the factory service manual and to my amusement, the sender is an on-off switch! This is a 1994 F-series. Ford went to the expense of putting an acutual gauge in the dash cluster, then added a 20 ohm resisor to put the needle in the "normal" range when the circuit is grounded. What kind of "better idea" engineering is this? Jim

[mantta]

My 88 was like that. I found an article on this site on what sender to install and to clip the resistor out of the circuit behind the dash. Mine now reads the oil pressure. I dont know how accurate the gage is though. I checked it at idle, warm with a real mechanical gage and I had 50 psi.

[restorit]

According to previous posts, I believe it was around '86. Apparently, Ford was getting frustrated with the amount of warranty complaints they were getting from customers who did not understand that lower oil pressure in a warm, idling vehicle was to be considered normal. The solution? Don't let the customer know that the oil pressure is lower! I guess the light wouldn't have been as cosmetic..... !

[jimandmandy]

I just got the real sender from Ford. SW-1547-B and E4ZZ-9278-A are the part numbers printed on the box. The thing is huge and requires an extra fitting to install it. On my '94 302 the sender location is right next to the oil filter. There is not much clearance on a 4x4, but I will find room. I did not find anything in the Tech Articles on this site, so I'm on my own. I have to shunt the resistor on the instrument cluster printed circuit. There is a picture of it in the shop manual. According to the parts guy, only high-performance vehcles, like the Mustang Cobra and Thunderbird SC got the real one.

Jim

[AlM]

YO,
here you go:
http://www.ford-diesel.com/contents/getitems.php3?Real%20Oil%20Pressure%20Gauge%202

[padutch]