Some of you may remember my threads about oil pressure. Well... I never noticed this until recently, but when I turn the car to "ON" with out actually starting the car; the oil pressure gauge moves to near high. Now this cant be normal. The engine isn't even on. There should be no oil pressure. What's up with that?
I just replaced the oil pressure sender, and for all I know the gauge works fine.
Every classic Mustang I've owned has done that, I wouldn't worry about it unless it doesn't normalize after the car is started. I believe it is the instrument voltage regulator that hangs a little upon startup. The IVR uses bi-metal contacts that switch off and on at a specific rate to regulate voltage to the instruments. I think the contacts need to heat up a little before they start working properly.
Does it just do this on the oil pressure gauge? If so you may have a bad sender, wire, or gauge.
The oil pressure, fuel, and temp. gauges are all identical internally (at least 65-66 & 67-68) so you should be able to move the sender wire from the oil pressure gauge to the temp or fuel gauge and determine if it is the gauge, wire, or the sender.
When you wired it to the water temp sender and you say the gauge worked fine then I would have to point to the oil pressure sender, even though you already replaced it. If you pull the wire off or the oil pressure sender (make sure it doesn't get grounded), does it drop to L? If so it is the sender, if not it is the wire. I know you've replaced these items already, but sh!t happens /forums/images/icons/smile.gif
I just saw your edit. You can test the gauge (hot or not) by pulling the wire from the sender. If the sender wire is off the sender and not grounded your gauge should read L, if you ground the sender wire you gauge should read H. If this works your gauge and wire are good. If this doesn't work you need to pull the wire off of the gauge and check it for a short to ground, if that is good than it is the gauge.
I did your test... read L when I took the wire off the sender and H when I grounded the wire.
So it must be the oil pressure sender then. Arg, I just bought it.
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Related Threads
?
?
?
?
?
Vintage Mustang Forums
4M posts
89.4K members
Since 2001
A forum community dedicated to vintage Ford Mustang owners and enthusiasts. Come join the discussion about restoration, modifications, NOS parts, troubleshooting, VIN codes, and more!