I have a 2004 Jeep Grand Cherokee Laredo V8. Was sitting at an intersection and the oil pressure just went to zero and my "check gages" light when on. I checked the oil the day before and oil level was fine. Anyways, in the parking lot i happened to have a quart of oil in my jeep that i dumped in. Feeling risky i started it up and the guage stayed good for a bit and then dropped back down. Feeling even more risky and desperate to get home i decided to drive it 2 miles to get back home. As i drove the gauge almost routinely would dip to zero and the "check gages" light would come on. Then it would go back up to normal for a few seconds and go back down to zero for a few seconds. It continued to do this the entire two miles. You guys have any ideas? Its got about 169,000 miles on it, and i just put a brand new oil pan on it.

I also forgot to mention that I had been driving in rain pretty much the entire day. Didn't know if that could affect it someway, somehow.

When your Oil Pressure Light comes on, you can bet that there is a reason. It could be something as simple as being low on oil, or it could be an indication of serious engine problems. The trouble is, you don’t know whether the problem is serious or no big deal, so your best course of action is to pull over immediately and turn off your engine. This is because if your oil pressure goes down to nothing, you could damage your engine to the point where you will need significant repairs, and may even need to replace the engine. So, what causes your Oil Pressure Light to come on? It could be a number of things: Low oil level could be the cause. This is the simplest to correct – just top off your oil, see if the light goes out, and if it does, you can get back on the road. A faulty oil pump could also be the culprit. If the level on the dipstick is showing between “add” and “full,” and then engine was running noisily, you need to stop driving until the issue can be corrected. You could have a bad oil pump. On the other hand, if the level is between “add” and “full,” and then engine was running quietly, you could have a bad oil pressure sending unit, light switch, or oil pressure gauge. You can safely drive home and have this fixed, but if the engine starts to sound noisy, stop immediately and call for a tow truck. You could also have leaking gaskets or seals. You will need to top up your oil, and again, you can safely drive home. Make sure to get the oil seals or gaskets replaced, though, because if they give out all at once you could end up with a seized motor and very expensive repairs. Another possible cause could be worn engine bearings. If this is the case, you will probably need to have your engine rebuilt or replaced. So, is it safe to drive with the Oil Pressure Light on? Depending on the cause, you can probably drive safely for long enough to have the problem diagnosed and corrected by a qualified mechanic. At YourMechanic, we can diagnose why your Oil Pressure Light has come on and recommend a solution. Good luck

Possibly be your oil sending unit is old and on it's last leg and time to change it. If it was your oil pump it would have locked the motor up in that 2 miles.

You also mentioned that you had replaced the oil pan so I would check to see if there is any leaking around it and if the drain screw is set in properly and Not stripped causing oil to leak out. Be careful not to put too much oil in that can also cause more harm than good. It could be something simple as a bad gauge Good luck

It sounds like it's your oil pressure sender/switch, just like TheGuru69 said. I've seen that happen with trucks I've worked on and I replaced that part and it fixed the issue.