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Discussion Starter #1
Okay, here's the problem, my oil light came on after my PI swap. I finally got around to messing with it tonight. I unplugged the wire to the sending unit and the light went out. So I hooked it back up and the light came back on. I had already changed the sending unit twice before so it's not the sending unit. What would cause the light to be off with the wire disconnected but on when it's hooked up?
 

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Discussion Starter #3
No, it came on as soon as we started the engine after the swap. Why would the light go off with the wire disconnected though?
 

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assuming you actually have oil pressure, and im assuming you do. A sender with a light is simply a switch. The sender shorts to ground when there is no pressure, turning on the light. When the sender has pressure to it, the switch opens and the light goes out. You can test this by starting your engine and touching the sender wire to ground, the light should come on. I said all that to say this... It sounds like your sender is shorted or u somehow got a sender that's working backwards (shorted to ground w/ pressure)
 

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Discussion Starter #5
351, I hooked the sending wire to ground last night and no light. But still no light when it wasn't hooked to ground.
 

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Well, did you get the right switch? There are two types of switches, normally closed for cars with the oil light, and normally open for those cars that have an oil pressure gauge in the cluster. See if you have the wrong one by connecting the wire to the switch, and turning the ignition on. If the light is off with the engine not running but comes on when you start it, you've got the wrong switch.


Assuming you've verified there is good oil pressure, you'll need to check the circuit from the cluster to the switch. Using an ohmmeter and a long test lead, check first from the connection at the switch to the connector at the back of the cluster. Should be very low resistance there, and a stable reading. If it fluctuates when you move wires around, you most likely have a problem with corrosion or a loose terminal somewhere. If it checks out okay, then check resistance to ground from either end of that circuit after you disconnect it from the cluster and the switch. This should show infinitely high readings, indicating the wire is not shorted out somewhere. If it does show a reading, time to break out the flashlight and start looking for damage.

Good luck!
 

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Discussion Starter #8
I'm gonna go check here in a little bit but I'm almost positive the light is off with the ignition on and engine not running. Then comes on when the car is started.
 

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Discussion Starter #9
just checked it and yes the light is off with the ignition on and comes on immediately once I start the engine. Do you have the correct motorcraft part no for the sending unit that I need by chance Hotbird?
thanks, Kevin
 

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Discussion Starter #11

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Discussion Starter #13
Actually haven't got the part yet. It makes sense though, hindsight being 20/20 as it is I should have left the original one on when I did the swap and had the motor out. It was just one of those might as well change it while I can get at it easy, parts. Little did I know I'd be back under the car three more times trying to get the right one. I'll update once I get the part on. Thanks everyone for all the help!
Kevin
 

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Discussion Starter #14
Stopped by the ford dealer to see which sending unit I put on and it's the part no. chris gave me sw 2220 I think. I guess I'll just put on an actual oil guage. Does anybody have any suggestions for brands of oil pressur guages? I will probably mount it where the ashtray is currently. I guess I am looking for a guage small enough to fit there. Any ideas here guys?
thanks, Kevin
 

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Well, I'd say get an Autometer electric gauge in whatever style you prefer. They aren't that expensive as long as you don't get a real fancy Lunar series or something. I paid like $52 or so for my Phantom series gauge including sender, but if you don't want to spend that much then you can go with Autometer's cheaper lineup (Autogauge) or even go to your local parts store and pick up a Sunpro which will run you probably no more than $30. Those prices are for electric units, mechanical ones are quite a bit cheaper but I would never recommend one after having the line blow off of one and fill my a/c plenum with engine oil. :eek:

Please don't get the extremely cheap gauges from Wal-Mart, they are JUNK! :rolleyes: Sunpro is good if you don't want dead-on accuracy, but anything cheaper sucks!
 

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Discussion Starter #16
Well, I'd say get an Autometer electric gauge in whatever style you prefer. They aren't that expensive as long as you don't get a real fancy Lunar series or something. I paid like $52 or so for my Phantom series gauge including sender, but if you don't want to spend that much then you can go with Autometer's cheaper lineup (Autogauge) or even go to your local parts store and pick up a Sunpro which will run you probably no more than $30. Those prices are for electric units, mechanical ones are quite a bit cheaper but I would never recommend one after having the line blow off of one and fill my a/c plenum with engine oil. :eek:

Please don't get the extremely cheap gauges from Wal-Mart, they are JUNK! :rolleyes: Sunpro is good if you don't want dead-on accuracy, but anything cheaper sucks!
any chance you've got pics of how you mounted ur guage? I was thinking of powdercoating some aluminum panel material and putting it in where the ashtray is now. I don't really want it mounted on or under my dash, not really a fan of the a-pillar mounts either. So I guess I would like to see pics for ideas on custom mounts that anyone has come up with?
 
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