Have a question. I have an 89 vette with about 45k miles. Last summer I blew a water pump. The motor never overheated as I was relatively close to home when it happened. I swapped the pump out over the winter with no issues. I got it out of storage this week, and did my normal tune up and maintenance. Oil change, checked plugs, which I replaced, etc etc. Nothing crazy. When I fired it up today, my oil pressure gauge read 540. It has always said low. Always. I've never seen it display any numbers. It did drop to 440 when I briefly stepped on the gas once, but has been on 540 since. And this is at start up, cold. I haven't let it run for more than a minute yet because of this. I've had this car for years, and have never had any issues at all. None. The oil that I took out was a bit dark, but nothing concerning or out of the ordinary. I replaced it with the same synthetic oil I've always used. Same k&n oil filter. I don't want to let it get up to running temp because of this, as I don't want to turn this problem into a much bigger problem. Any suggestions or ideas as to what can cause this? It did sit a longer than normal, the pump blew out in June and I usually don't put it away until Octoberish, give or take the weather ofc. But I did start it periodically as I always do amd nothing seemed outnof then ordinary until now. Oh 1 more thing. Today after I started it and shut it back down, I heard a strange noise in the engine area. It was off, not running. It sounded like water was dripping on the headers. Just a slight, pssshh sound. Every 15-20 seconds. I couldn't find anything dripping or that looked wet at all. I did just wash the car, but didn't get any water under the hood. It lasted about 2 minutes then stopped completely. Pls let me know if anyone has any ideas.

 

I'm a little confused. The oil pressure gauge should never say "Lo". Oil temperature will say Lo until I believe about 110 F. So will Coolant temperature.

Was the ENG/MET switch in Metric? An oil pressure reading of "540" could be 540 Kpa which is 78psi. << Seems about right for cold oil.

The hissing after shutdown: If the A/C system was operating at the time of engine shut down, it will hiss until pressure equalizes across the orifice tube. Usually, the hiss is even (not every 20 seconds), and lasts about 15-20 seconds, depending.... << So probably not the A/C, but that's all I've got.

I don't think there is anything wrong to prevent you from driving it. Drive it. Watch the temperatures and pressures. Be sure the switch is in ENG[lish]. It's probably ok.

Welcome to the Corvette Forum.

 

I may b mistaken on the low, that may be the oil temp that said this. It's not switched to metric. That was then1st thing I checked. To be completely honest I rarely had it set to read pressure. Almost always temp. Idk why it's just where it usually is. I ofc flip it to check the pressure from time to time, and I know for a fact it's never read that. I'm gonna check the relieve valve, replace it along with the sensor, and use a manual gauge to check it as well. My biggest worry was it sitting longer than normal. I had a truck that sat for a year when I was younger end up needing a complete rebuild due to water ports rusting up. So I'm a bitnover cautious maybe

 

Caution, this is from my 87 and may be different for 89 but I dont think so.
There is a warning light next to the readout, it is square, was it on. There is a chance your are seeing a connector off somewhere and it may even be the oil temp, on my 87 the oil temp sensor is on the block near the oil filter. The reason you may be seeing the oil temp when the switch is in oil pressure is the cluster forces the out of range information onto the display reguardless of switch position. For instance, if the oil temp is out of tolerence the red light should come on and the display automatically shows oil temp no matter where the switch is. In order to display oil pressure in that condition, the switch has to be moved to the off position then to oil pressure, it will display pressure for 5 seconds before automatically being forced to display the faulty oil temp.
.