Okay Mazda geniuses,
This little niggle popped up today and then disappeared.
The Car: 2004 M6 Wagon 3.0, 167,000mi, ATX (JATCO 5spd). Oil: Castrol High Mileage syn/blend 5W20 (changed every 3000, currently with 1200mi), car will consume about 1 1/8-1 1/4 qt every change, same for 3yrs) No issues other than lower control arm bushing wear. pre-cats replaced at 126,000mi along with, PVC, COP's and Plugs.
Scenario: Making a 3-point turn on a slight slope I noticed a faint momentary flicker of the oil light when switching from R to D. I moved to park on flat ground and tried it again. D to R saw a faint momentary flicker of the oil light. I happened when I moved D -> R and R -> D. A momentary flicker (not enough to fully illuminate the light then gone. Checking the oil show a full pan with good color and smell.
Any ideas?
Thanks everyone for reading. Happy Holidays
Edit, this popped up again in Oct 2018 (180,000mi) and then again in Feb 2019 (both times at hot idle)
Start with the oil pressure switch, that is usually the suspect on older car. If that doesn't help, then i'm afraid the news is not very good. You either have sludge or an oil pump that is on its way out.
Oil Filter Sandwich Plate with OEM Pressure Sender
Hello again. I forgot I had posted this issue until I was searching for a solution to my next step.
The oil light started flickering at idle again and I have decided to move forward in trying to diagnose/remedy it.
I cannot take my OEM oil pressure switch (OPS) out for mechanical pressure testing because the previous owner stripped it in place. It does not leak and I am not touching it again. I do however want to verify the oil pressure is adequate, and if so, extinguish my epileptic oil pressure light at the same time.
I have purchased an oil pressure sandwich plate (M22 - 1.5) from GlowShift. There are 4 ports (3/8"-24) on the plate and I would like to put a new OEM sender switch (and possibly temperature and pressure gauges) which is a M14 x 1.5 pitch)
The symptom has been presenting itself sporadically(3x) for over 2 years so it is not likely moving very fast but I will still verify actual pressure using one of the plate ports before investing in a gauge set.
I need to put a (Male) M14 x 1.5 (OPS) into a (Female) 3/8"-24 (sandwich plate). An adapter for this does not exist.
My options as I see them are:
1. Try tapping a [3/8"-24 to 9/16"-18] to a [3/8"-24 to M14 x 1.5). Not sure if I can go 9/16-18 to M14x1.5 but something like that.
2. Try finding a compatible sender that will fit the sandwich plate and send appropriate voltage to keep light off (voltage unknown).
3. Run a mechanical gauge and cut the LED off the speedometer instrument board.
What I want is the OEM sender communicating with the light as it is supposed to and possibly running gauges as well.
Could I use the oil pressure sender supplied with a gauge to communicate with my OEM oil light?
Any thoughts/suggestions people may have are welcome.
@DrFeelGood I don’t think that the aftermarket sender would work with the OEM system my reasoning here is that the OE switch is, I believe, basically an on/off switch set at specific pressure by the factory, while the aftermarket one is designed to report the exact pressure.
@DrFeelGood I don’t think that the aftermarket sender would work with the OEM system my reasoning here is that the OE switch is, I believe, basically an on/off switch set at specific pressure by the factory, while the aftermarket one is designed to report the exact pressure.
Well... I'm only vaguely familiar with the particulars of your sandwich plate @DrFeelGood , but given the discussions above, my recommendation would be to buy a new mazda sending unit/switch and use that in your sandwich plate so you're sending the same data to that wire.
My guess on the sender is that it is a resistance to ground that the sender manipulates to register a value. If it is just a simple pressure switch then I'd guess grounding it would keep the light off. Have you tried removing the wire while the engine is running to see what change there is with the light on the dash? I will say, these are all speculations at this point, but that's how I would go about it.
Hey @waughoo thanks for responding. I got into the wiring diagram a little yesterday and the Google to see how they operate and it is likely a pressure operated on/off switch. I'm guessing, (will verify soon) that with no pressure the circuit is closed and the light illuminates. Pressure in the system separates the contacs and the circuit opens, (light goes out). Since there is no fuel cut off associated with it I bet just disconnecting the unit will open the circuit and quell the light.
I will post my verification back here after.
So great to verify that you have solid oil pressure. My vote is for a drill and tap with the original sensor to keep your oil warning light functionality.
Happy to hear that your problem is only the sender.
For anyone else that has to do this his numbers confirm that if you use the ports on the rear head for an oil pressure reading they are just as accurate, all of his numbers are within +/- 2 psi of mine (I use the the front port on the rear head for my gauge)
For anyone else that has to do this his numbers confirm that if you use the ports on the rear head for an oil pressure reading they are just as accurate, all of his numbers are within +/- 2 psi of mine (I use the the rearward port on the rear head for my gauge)