oil pressure gauge freak out

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guitarfreak235

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my oil pressure gauge is constantly reading 14 when the engine is cranked but every once in a while it will read a more normal pressure. one time i caught it going back and forth between the usual 14 and a higher reading, it began to switch back and forth wildly if I reved it a little. Any ideas? does this sound like the gauge itself is bad or something else??
 

bucket

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When I have one act up, I usually try the sending unit first (fixed em all so far). It's just a guess, but they are always leaking a bit of oil and I want to change them anyway.
 

chengny

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Behind the distributor (and a bit toward the driver's side) there is a brass pipe fitting with 2 sensors screwed into it. The one with the dome shaped housing (single wire connection) is the variable resistance sender for the oil pressure gauge. Check that the connection is tight and inspect whatever part of the wire is visisble (look for broken insulation).

If the wiring/connector are alright you might need a new pressure sender. They aren't too expensive - maybe 15$.

To isolate the problem to the sender do this:

With the dash instrument panel hot (key in the on position) pull the wire off the big pressure sender. With someone watching the gauge, touch the connector to any bare metal on the engine. The dash gauge will peg (high I think) if everything other than the sender is okay.




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crazy4offroad

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Behind the distributor (and a bit toward the driver's side) there is a brass pipe fitting with 2 sensors screwed into it. The one with the dome shaped housing (single wire connection) is the variable resistance sender for the oil pressure gauge.
Mine is located down by the oil filter, so was the 83 K1500 I had not so long ago.
 

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