Oil Pressure Gauge Very Low on Start-up

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FadeToGray

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When I started up my Jeep today, it threw the "check gauges" warning at me, and I noticed the oil pressure gauge was way low.

I shut it off, there was oil in there, and things seemed ok.

So I started it back up, and everything was fine. So check gauges warning, and the oil gauge read where it was supposed to be.

I've been driving it today, and have turned it on and off several times, and it seems fine.

Anything else I should check or be concerned about? Maybe a fluke thing or error with the gauge?
 
Sounds like it could be the sending unit or that the two big connections on the back of the instrument cluster need to be cleaned. Do an Instrument Cluster Diagnostic test and see what comes up
 
X2 to the above. The sending units commonly go bad.

I'll also add that the factory oil pressure gauge is notoriously inaccurate.
 
Replace the oil pressure sender located next to the oil filter with a Mopar replacement. Avoid store-brand oil pressure senders which are notorious for not working properly or not working properly for long.
 
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Jerry Bransford said:
Replace the oil pressure sender located next to the oil filter with a Mopar replacement. Avoid store-brand oil pressure senders which are notorious for not working properly or not working properly for long.
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Jerry, could the same be said for the temperature sensor? I've had, on a couple of occasions, the temp gauge hit the 260 mark, only to return to normal operating temp after a few moments. The coolant has never boiled over, and I'm not losing antifreeze. After the first occurrence, I changed the thermostat, hoses, and flushed coolant, but the issue has happened a few more times since. I haven't tried replacing the temp sensor.
 
Dave a sudden/quick temperature spike like you described is more likely caused by a sticking/defective thermostat. I'd replace it with a new good quality 195 degree thermostat like from Stant. Stant's SuperStat is a great choice. Make sure NOT to install any thermostat claiming to be "fail safe" which just tends to fail more often in the open position.
 
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Could be having ground issues. Clean your battery terminals, check your cable ends where they connect to the frame or engine, and make sure the body has a good ground connection to the frame and motor.
 
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And also check all the sensor connections. A bit of dielectric grease can help keep out some gremlins.👿 any time you disconnect part of the wiring harness clean and a dab of dielectric grease will keep rust and grunge away.
 
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Jerry Bransford said:
Dave a sudden/quick temperature spike like you described is more likely caused by a sticking/defective thermostat. I'd replace it with a new good quality 195 degree thermostat like from Stant. Stant's SuperStat is a great choice. Make sure NOT to install any thermostat claiming to be "fail safe" which just tends to fail more often in the open position.
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Thanks, Jerry. I did replace the t-stat when it first happened, but don't remember what brand I used. I'll pick up a Stant thermostat and give that try.
 
Goatman said:
And also check all the sensor connections. A bit of dielectric grease can help keep out some gremlins.👿 any time you disconnect part of the wiring harness clean and a dab of dielectric grease will keep rust and grunge away.
Click to expand...
Thank you. I will give that a shot. Still have plenty of dielectric grease leftover from when I replaced the O2 sensors.
 
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