Mazda Miata 93 High Oil Pressure Gauge When Engine Is Not Warmed Up.
Posted in Crank, Oil and Piston | Asked on Jun 16, 2010
Below is the question about Mazda Miata 93 High Oil Pressure Gauge When Engine Is Not Warmed Up., First problem, the oil pressure gauge is very high, at 6 when the engine is jsut turned on and with the aircon on, but when temperature reaches normal level, the oil pressures returns at 4 when idle with aircon.. what could be the problem? also, when the lights are on, the oil pressure gauge moves up, and when you switch the power window, it also moves up and down.. could it be lectrical, what part? also my car overheats but the coolant isn’t boiling and the water is at the same level, this usually heppens during highway driving with high RPM and the aircon is on.
There are 4 Answers for "Mazda Miata 93 High Oil Pressure Gauge When Engine Is Not Warmed Up."
It is normal for oil pressure to be lower at idle with a warm engine. If the oil pressure use to always stay at higher levels,you might try putting in a new oil sending unit. I would have my coolant system pressure checked. You may need a new radiator cap, or even a new radiator. The car is fairly old. The radiator my be clogged.
Lets adress your questions I at a time.
When your engine is cold the oil is thicker and thus you will get a higher reading. When you rev the engine the oil pump spins faster thus creating more pressure, sond like that is acting normal.
Everything on that car is electronic. If you have a weak battery and the generater is doing all the work you will get small glitches like that. Also a bad voltage regulator will cause th same issue unfortunately it is in the generator, take the car to a chain store(Autozone, Advanced, Pep Boys,) and have them do an electrical systems check for free that will tell you if its the alternator or battery.
If you have low fluid levels it the radiator that will cause it to over heat while driving. Also check and make sure the cooling fan is working properly, you may have to repace the fan or a relay. Another thing to check is the waterpump, Locate the water pump and grab the pully(while the engine is off of course) and see if there is any play in it. Push it in and oull it out and side to side, if there is any play, it is bad.
If it only doing it with the air on it sound like a fan problem to me or mabbe a thermostat. to be safe check everything though, it could save you having to replace a head gasket
is normal for the oil pressure go up and down because the pump is mechanical so high rpm at the morning to warm up means high pressure once it reach normal temp the pressure goes down, when you turn on the lights the alternator has to work harder so the ecu know that and send more fuel to raise the rpm to prevent the engine turns off at idle and to compensate the loost of power in normal driving, so thats why the pressure goes up, if you are not satisfied you can change the pressure sender to make sure you are getting a correct signal
the second problem could be the a/c when the compressor is not working properly it tends to overheat the car, but overheating problems are not that easy to find unless you change all the components one by one but in this case start changing all temp senders and thermostat
once you change those things, flush the system with a 5 min flush can, add new coolant with the correct mixture if that doesnt help you need to change parts like hoses, radiator, fan motors or water pump
I am not sure that the 93 has a true oil gauge. There is a year that Mazda changed to what is in all reality an idiot light and masked the change with what appears to be a pressure gauge.
On both my Miata’s the pressure drops after the engine warms up. If I was worried about it, I would go to a 10w-50 oil. With a worn engine, the pressure would increase as the engine warms up, not drop.
The over heating is most likely the fan relay. Just went through this with my 90 Miata’s.