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Oil Light

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K

KSIS

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I'm a little concerned. The oil light on my 64 Spit is on all the time. The only time it is out is at a really low idle when I first start it.I redid the dash and since then it has been on. I checked the connection and all is good. The light worked fine before I did the work. I dont have a pressure gauge but I can see oil being pumped to the lifters.
Any thought.
 
I would get a remote gauge and check it

But that is kind of bass ackward. Light off at idle and on at cruise.
 
It's a pretty simple circuit. A white wire comes off the #2 terminal of the ignition stiwch and goes to one side of the warning lamp. A white w/brown trace wire goes from the lamp to the oil pressure switch, which in turn is (perhaps obviously) grounded to the engine. There's not much that can go wrong with that circuit other than the sender failing...which seems like an incredible coincidence, but I suppose anything's possible!

This from the US-spec. Mk2 wiring diagram.
 
I know its a simple circut, hence the confusion. I'm thinking the sending unit is bad. It was leaking a little and I tightened it up. maybe that was just enought to cause a problem. Thanks for the info!!!
 
Yeah...you may have "finished it off" when you tightened it, or maybe it was already bad. I've had several of those senders fail in one way or another, and typical "failure mode" seems to be leaving the light illuminated all the time. :frown:
 
Andrew Mace said:
and typical "failure mode" seems to be leaving the light illuminated all the time. :frown:
Click to expand...

That was probably someone's idea of "fail safe" in that if the sender fails you get an oil light, you will stop the engine and look for the problem. The engine lives to fight an other day. If on the other hand the failure mode was to leave the light off then you could get a situation where the oil does stop to flow and you would not know it since the sender is open and failed. The engine does not live to fight an other day.

maybe I over analyzed this one :smile:
 
That was my thinking. The light stays on telling you everything is good. When the light went out you had a problem.
Wel the problem was a broken wire and a bad unit. So now all is well. I had a spare sending unit from an aold VW. I plugged it in and grounded it to the frame with the key turned. No light.
Traced the wire and found a crack. Replaced the wire and the unit worked. Plugged in the old one and no light. Ran down to the local Ap, and found a single pronged unit from a 92 Camaro. It has a longer body but for 5.99, how could I go wrong.
 
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