engine oil pressure problem

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Hi, I've probably already have asked this but I recently changed out my oil and the gauge started to act wonking the needle is jumping after driving awhile when warming up and driving for 20-25mins the psi stays at 60 but after awhile it will go to 90, 120, and 140 when stopping at a light but as soon as driving it goes back down to 60. I changed my oil pump and cleaned out the new one took it apart and everything nothing is in the oil pan because I figured if the feeder is stuck it would be losing pressure not gaining or if the relief valve was stuck or opened but I've been reseraching if their was high oil pressure it would of blown the oil filter off clean with those spikes but it hasn't happened (knock on wood) so im thinking that the gauge or sensor is faulty has anybody had this problem before
 

mopar440

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Check it with a manuel gauge, you think it would have blown the filter off. Using a good filter? Not fram?
 

cbarge

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Unless you have a cop car majority of c bodies did not have a factory oil pressure guage ( Imperials did).
If you are running an aftermarket oil pressure gauge, as mentioned do a remote oil pressure test.
I am betting a faulty sender or the gauge if all electric is wired wrong.
I prefer using a guage with an oil line feeding it through the firewall.
Hope this helps.
 
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Unless you have a cop car majority of c bodies did not have a factory oil pressure guage ( Imperials did).
If you are running an aftermarket oil pressure gauge, as mentioned do a remote oil pressure test.
I am betting a faulty sender or the gauge if all electric is wired wrong.
I prefer using a guage with an oil line feeding it through the firewall.
Hope this helps.
Aftermarket guages and the wiring was done professionally I would never do all the other guages are working probably just the oil pressure is bouncing i was thinking the same faulty sender or a bad ground
 

CBODY67

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Considering that an electric gauge works by a variable-resistance ground type circuit (i.e., fuel gauge sort of arrangement), then ANY flakiness in the electrics of the gauge can be suspect. Especially IF they rely upon the gauge body/holder to complete the ground circuit of the gauge. Which might also relate to alternator output/function at the affected rpm levels when the gauge reads inconsistently. Which might possibly explain that when the car is moving at a reasonably steady speed, all is good, but when the rpm drops at idle (which might mean more voltage regulator action), then things appear to get flaky as the voltage regulator works more?

The ultimate test is to screw a manual gauge into the hole where the pressure sensor now is and see how it acts and what the pressure is at various (spec) rpm levels . . . with USED motor oil in the engine, not fresh, with the engine fully warmed-up. If all of that checks out as it should, then start chasing wiring gremlins in your aftermarket gauge system. Starting with the integrity of the gauge panel attachment to whatever it attaches to. Running an extra ground wire might be all it needs, past a new sending unit? Resistance of any crimped (un-soldered or incorrectly soldered) connections in the circuit would also need scrutiny.

Keep us posted on how things progress, please.

Just some thoughts,
CBODY67
 
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Considering that an electric gauge works by a variable-resistance ground type circuit (i.e., fuel gauge sort of arrangement), then ANY flakiness in the electrics of the gauge can be suspect. Especially IF they rely upon the gauge body/holder to complete the ground circuit of the gauge. Which might also relate to alternator output/function at the affected rpm levels when the gauge reads inconsistently. Which might possibly explain that when the car is moving at a reasonably steady speed, all is good, but when the rpm drops at idle (which might mean more voltage regulator action), then things appear to get flaky as the voltage regulator works more?

The ultimate test is to screw a manual gauge into the hole where the pressure sensor now is and see how it acts and what the pressure is at various (spec) rpm levels . . . with USED motor oil in the engine, not fresh, with the engine fully warmed-up. If all of that checks out as it should, then start chasing wiring gremlins in your aftermarket gauge system. Starting with the integrity of the gauge panel attachment to whatever it attaches to. Running an extra ground wire might be all it needs, past a new sending unit? Resistance of any crimped (un-soldered or incorrectly soldered) connections in the circuit would also need scrutiny.

Keep us posted on how things progress, please.

Just some thoughts,
CBODY67
So this weekend swapped the oil pump opened up the new one cleaned it out before installing changed oil filter and dropped the oil pan nothing in it nothing blocking the oil feeder so that leaves the gauge and the sending unit left did notice at high rpm is when it stays a consistent psi and when rpm lower that’s when the gauge goes high. So this weekend im going to change out the sending unit and if that doesn’t work then it’s the gauge itself
 

Snotty

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Stop feeding it so much salt!! That's always bad for blood pressure!!

Oh... wait... oil??
 
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