Hi guys,
I’ve recently installed the proper oil pressure sensor from the NA on my NB. I’ve been testing it out with a digital oil pressure gauge. I’m getting very weird readings.
The digital oil pressure gauge I purchased came with its own sensor. With it, at idle, i’m getting 43-45. However, when I use the original MX-5 Mk1 sensor, I’m getting about 10 at idle (warning light from the oil pressure gauge lights up)
http://www.ebay.co.uk/itm/151991497259?_trksid=p2057872.m2749.l2649&var=451171673506&ssPageName=STRK%3AMEBIDX%3AIT
Either one sensoris faulty. Hopefully its the ebay gauge as its from China. The car has 3/4 oil.
Digital Pressure Gauge + its own sensor
Idle 43-45
Digital Pressure Gauge + MK1 sensor
Idle 10 (warning light on gauge comes on)
Does anyone know whats the recommended oil pressure for a NB 1.8? I apologize if this has been asked before.
Regards,
Jiv
The sensor and the gauge need to be a matched pair so the reading of 45 looks reasonable. By using the Mazda sensor with another manufacturers gauge you may get a wrong reading and it looks likely that is what you are experiencing.
To get a more accurate reading you really need a capillary set up, these people are experts in this field have a look here. http://www.thinkauto.com/acatalog/On_line_shop_Dashboard_Instruments_345.html
The electrical ones are notorious for sender failure.
The senders work by varying their electrical resistance with changing oil pressure. So the sender and gauge do need to be matched as per the manufacturer’s design. If you mix them up, the readings will be meaningless.
Darn, I didnt realize you cant mix and match sensors with gauges. The NA sensor is definitely not working with the gauge. I’m getting lower pressure when I rev up the engine.
Do you guys think its okay for me to just use the sensor from the ebay seller? I’m not sure what brand it is.
Also, I’m kinda confused, some people have been recommending the trackdog vdo360-009 sensor. Would that work with this gauge or only with the mx-5 gauge?
Mad Malc - What do you mean by ‘The electrical ones are notorious for sender failure.’? Are the electrical gauges known for damaging the sensor? Should I just go for a mechanical gauge to fit the NA sensor?
One last thing guys, is anyone able to get the recommended operating pressure on an NB? I cant seem to find it and want to know what pressure I should be expecting at idle and normal driving.
The sensors are directly attached to the block as you know so are subject to all the vibrations from the engine. These vibrations can change the way the sensor reacts so the readings can become unreliable. Common symptoms of a poor sender are, but not limited to: low reading or wildly fluctuating readings and often varying as the engine warms up…
The mechanical gauge uses a capillary tube to directly connect the oil passage (where your current electrical sensor is attached) to the gauge. There are no electrical connection other than the illumination lamp with this type of instrument. The actual pressure exerted by the oil is measured. It is therefor more consistent and usually more accurate than the electrical type.
It would make sense in your case to use the parts as supplied, Do not mix and match as confusion may result.
From the Haynes Manual: 1.6 & 1.8 @ 1,000 rpm = 29 to 42 psi
@ 3,000 rpm = 43 to 56 psi
2.0 @ 3,000 rpm = 49 to 85 psi
All the above with a warm engine.
Thanks a lot Mad Malc.
Is there any digital gauge that will work with the NA’s sensor and a VDO 360-009 (thinking of using this if the NA’s sensor is screwed). If not, can I clarify something? Would ANY mechanical gauge work with the NA/VDO sender or do I need a specific one too?
Thanks again!
Regards,
Jiv
A mechanical gauge doesn’t have a sender. There is actually oil in the capillary tube, it connects to an oil gallery on the engine block. The oil pressure changes the curvature of a coiled tube in the back of the gauge. The gauge pointer needle is connected to the coiled tube by a simple gear and lever system. As the oil pressure in the capillary tube increases, the coiled tube unwinds, moving the needle across the scale. With no pressure, the coils returns to its original shape.
Thanks a lot Paul! I finally understand it a bit better!
I kept mixing up Mechanical gauges with analog gauges. I just assumed analogue gauges = mechanical (the ones on the mx5). Turns out the mechincal gauge, comes with a hose and plugs straight into the engine.
So my choices are basically
1) Stick with the current digital gauge with its sender.
2) Get the TrackDog Racing Unit and plug it straight to the MX5 NB’s gauge
3) Play around with resistors and get the NA’s sender to work with the NB’s gauge.
If I go with the digital gauge, I’m kinda tempted to get a oil temperature gauge to go along with it. (looks too weird alone). Or maybe a gauge like this
http://www.thinkauto.com/acatalog/OPOTG.jpg
Also, if I stuck with the digital gauge, what could I do with the current gauge on the NB’s cluster? turn it into a clock?
