oil pressure guage was at almost zero!
 

Hello I'm new.

I have a First Generation 85 RX7 with 56k miles. Today I warmend my car up, but a little less than I usually do and was prepared to drive it easy for a few minutes. I looked down and the oil pressure guage was at almost zero! Ahh it's usually 30-60. I am going to admit that I'm over on changing the oil, which I am going to do right after work. I read about using a really thin oil to clean it out and then switching back to full synthetic (before driving), also I understand that my sending unit may be bad. The strange thing is that at idle is't almost 30, but then when I drive it goes down to almost zero.

I'm afraid to drive to work!

p.s. I changed the starter last week, but I doubt that is related.

In case anyone is interested I did solve this problem, or at least I think I did. I drained the oil and ran a cleaner that the guy at autozone and I decided was safe for the rotary engine (I hope it is), then replaced with a fully synthetic oil (which I have heard different opinions about using). I also jacked the car up and cleaned the buttom of any oil gunk, and then I drove the hell out of it.

Oil pressure back up, though it took about 30 minutes of driving.

What was the product? My car was sitting for a few years and am having low oil pressure readings also. I'm thinking of dropping the oil pan, cleaning out the pickup tube, checking the regulator and running something through it also.
This is the only thing keeping me from my first drive on this car.

It was sea foam. I put it in with the old oil and let it run for like 15 minutes, I then pushed the car into the garage to drain and replace the oil. I don't know what would happen if you drove with the addative in, but I thought it prudent to not find out. And like I said, it took a little driving for the oil pressure to regulate. I did a bit of research on this first and if your car was sitting, and the sending unit is original it might be bad.

I would like to hear thoughts on using fully synthetic oil. Guys from a pre '64 car club in Detroit told me to only use synthetic, but then I've run into people here in Austin who wouldn't use synthetic oil in a rotary. It seems to run a lot smoother and warm up faster with synthetic, but that is just my opinion.

Running smoother and warming up faster are likely in your head, although depending on the viscosity it may happen.

On my 86 (2nd Gen) I was having my gauge read at near 0 and all I had to do was clean it. The clip had gotten a bunch of grime and such in there. I'm not sure the setup of the 1st Gen, but it's probably something good to check.

I actually did get an oil with a higher viscosity level since it's cooler here in Texas, than it was a couple of months ago.

Also, when readying my repair manual it noted cleaning the clip and wires that run near the oil pan to the guage.

Glad you got it fixed and it wasn't a real problem. Using a synthetic is a good idea especially if you go over a bit. Just about everything about a synthetic is better than dino oil but there are many opinions, theories, etc. But my thoughts are that most brand name oils are pretty good nowadays (including non synthetics) so just pick one and change it every 3,000 miles.

Just make sure you premix your fuel if you can and never drive the car over 3,000 RPM (give or take) unless it is full warmed up (oil temp gauge is good for this). And also remember that if you do a lot of short trips, the moisture and other contaminants in the oil may not be getting burnt off because your engine oil is never really reaching the burn off point for a decent amount of time.