falcon63

I've got an 88 vert w/ 186K miles. When I start it cold(no smoke by the way), the oil pressure gauge reads 60+ psi. As I drive away, the pressure gradually drops to 20-30 psi. Again, no blue or white smoke, no noises, no low pressure idiot light, and it revs all the way to redline with only occasional 3800 rpm miss. It's full of Castrol 20-50, and needs a quart about every 1500 miles. I drive it everyday on the highway for 45 miles one way to work. The gauge stays at 20-30 psi while driving. Do I have a mechanical problem or an electrical one. Looking at the gauges it seems ready to blow. If I put tape over the gauge, I'd swear that I was driving a fresh engine. Help please.

freemanrx7

It is common to have oil drip on the sensor and cause faulty readings.

Try cleaning the connector. It is located right under the oilfilter. The sensor itself is about the size of a golfball and has a wire attached to it. Disconnect the wire and clean. Hope that helps

Roarke

My gauge seems to get that low, but if I rev it up it goes right back up high. Under normal driving conditions, it does get down there though.
Is that not normal?
I just got my RX.. and just got it all working

ericgrau

iTrader: (1)

Lol this is totally normal. Should be around 60 psi not too much above idle, around 30 psi at idle. And the gauge isn't very accurate, so don't worry if it's off a bit. Or you could try cleaning the sensor like freeman says and see if that helps. When you first start your car it "idles" around 2000rpm (give or take) so the oil pressure is around 60psi. If you really want to be sure you can buy a (more accurate) external gauge and check your oil pressure.

I think piston engines are the same. Do your other cars have more accurate gauges? Do they go straight to a normal, low idle when you first start them? Do they not have oil pressure gauges?

The oil metering pump injects oil into the rotary engine. IIRC normal oil consumption, without any leaks, is anywhere from 1000 to 3000 miles per quart. If you really want to check for leaks you could clean your engine bay until it's spotless then check for oil stains a few thousand miles later.

falcon63

My Porsche has both an oil pressure and oil level gauge that are extremely accurate. At start up it shows 5 bar and at operating temp and 3000 rpm it shows 3-4 bar. at idle it reads 1 bar because it's a dry sump system. I'm concerned with the drop in the RX 7 because it reads correctly at start up but drops off drastically as it warms up. The Mazda shop manual states that it should read 64-78 psi at operating temp and 3000 rpm. I'll go along with freeman's suggestion because we have 20 year old wires, connectors, grounds, etc, but I'm also wondering if we might have a mechanical problem concerning the oil pressure control valve or the oil pressure regulator valve shown on page 2-2. Has anyone else experienced this problem and might have a solution???

HAILERS

Your not clear.

IF after the engine is fully hot, and your driving at say a steady 3000 rpm, and your psi is in the 20-30 psi range, then it's most likely a front cover o'ring problem. Replace same.

I"d buy a aftermarket MECHANICAL gauge, like a SunPro for twenty bucks, and confirm the low pressure. Then replace the front cover o'ring.

falcon63

Thank you Hailers. I will confirm the pressure with a mechanical gauge and go from there, but what do you think of the possibility of the control and regulator valves shown on page 2-2 of the shop manual?

falcon63

Searched and found a post from BigWoogie in 2002 which seems to describe my problem exactly. it referred me to Mazdatrix and front cover o-ring replacement.

What the H*** we would rotary drivers do without the RX7Club??? There are no technicians at the Mazda agencies or independent shops that know enough about these cars compared to the collective knowledge of this group.

All hail all of you and thanks

Roarke

In spite of good cheer I must agree with your last post. I think if this club didn't exist, it would be made. Otherwise all RX-7's would just die and no one would know how to fix them.

lol

Very thankfully, this club and its members are here and its rockin!

Roarke