So today on my way to work sitting at a light the dash started buzzing, no lights came on and all the gages looked fine(temp doesn't work, but it wasn't hot and it was only after 10 minutes so could't have been that). Light turned green I went and the buzzing stopped. Next light same thing but I noticed the oil pressure gauge go down to 30 from 60+ psi, went I reved it pressure went up again and buzzing stopped. I pulled into a parking lot and left it.

So tonight I picked it up and it ran normal no buzzing until almost home. When I was testing it out in my driveway it started buzzing even before I started the engine(aux on) and the add coolant light came on(has been comming on randomly even though coolant isn't low) and when I did turn it on the revving didn't stop the buzzing.

This is an 1986 nonturbo 118000 miles I've had it for almost 2 months and this is the first real problem I've had, other than running out of gas yesterday on the way to work.

The only recent work I did was change the oil(put in 10w 40) and oil filter. I got a new oil pressure sender I heard that could be the problem so I'll try that tomarow and maybe it's the oil could have been thicker before I don't know. Any ideas?

 

It is your coolant buzzer. Make sure your coolant isnt low. (both radiator and filler caps). If not, then you have a bad sensor.

 

It is probly the oil level sensor. There is a buzzer for that to i believe. Judging by the oil pressure drop it is probly that.

 

30 psi on the gauge should be fine so it's probably not that oil. But check anyway. It takes like 20 seconds.

Its probably the coolant hasn't been filled properly and there is an air pocket at the top of the rad. You need to open the little hole on the end of your rad with a phillips head and pour the watter in until that is full.

Not all rx7s have the two capped system. S4s came with just the one on the thermo housing.

 

oh and check your rad cap, if its not sucking the water out of the overflow tank that will also cause an air pocket.

 

Oil pressure sounds normal to me!

Check your coolant dude. Squeeze the top radiator hose while the TOP cap is off. This will help get the bubbles out.

 

not true S4's had two caps one on the rad and one on the t-stat pipe. S5's had just one on the rad .

 

Low oil or low coolant.

And the Oil pressure gauge has nothing to do with the oil LEVEL

 

That low coolant buzzer was the only thing that saved my engine, because my oil pressure gauge doesn't work.

I was going home after some spirited driving and it kept going off, I'd make a turn and it'd stay off for a while then come back again. So I pull off in a parking lot only to find out my oil cooler line has burst! So I bought 3 quarts of 20w50 and stopped to fill up ever time the buzzer went off so I could get home.lol

 

Unless you have NO oil, which means you will have NO pressure.