Check guage / No oil pressure on idle
 

Hi guys, as it says in the title.Was driving back today from work sitting in traffic, suddenly see that check guage light is on, checked all gauges all fine except the oil pressure was down.As soon as I started driving again or gave it a little bit of throttle the pressure would rise and light would go off.It's 1998 v6 auto47k miles It was sat for a few years until I brought it and she's done 10k miles in the last two years.​​​checked for codes as eml is on, but I've had that on for a wwhile due to an evap system.I have just gone out to check oil, oil was bang on max, there's no funny noises from engine or anything different to how its been since ive had it.i did start the car up and the oil pressure was back to normal. I have Read through the threads but none of them relate completely to my issue .
just wanted to know if anyone else has come across this and if there is any known symptoms?

​​​​​​​Cheers
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Sounds like a connection or a gage issue. Also if the oil has gotten hot or is very old it can cause a pressure drop when the car gets hot. Sitting it traffic is about as hot as it gets.

My 2000 Z28 would do a similar thing after about an hour of driving. As I was going around a corner then it started working again in a minute or two. For me it was oil and fuel with no other symptoms. It would only do it once a month or less and it would only last one to two minutes. Even as a X GM mechanic I knew it was going to be a nightmare to track down because of all of the connections, the gage cluster and the Body control module possible issue. I fixed the issue by driving the car into a wall a 80 MPH. Never gave me an issue after that. Well that was not the reason for driving the car into the wall but either way it made the issue go away.

oil pressure switch/sensor is common failure with 3.8. low cost to just replace. had one on the 2000 go and went to 0 and then it started dumping oil out at the switch/sensor at the front of the motor.

​​​​​​​I did check the sensor incase the seal was no good but the inside was bone dry.​​​​​​​I'll replace it anyway and hope that's all it is.​​​​​​​Cheers

Try replacing the oil pressure switch (sending unit), they can go bad and it's a cheap part to replace. If you see oil in the plug when you remove it from the switch, it's bad without a doubt.