DocBeech

iTrader: (1)

I would like to start a thread where everyone can discuss the accuracy of the gauges they have. A couple of things must be understood first though. Gauge accuracy/calibration can be off for a number of reasons. I am looking for tested results not OBDII vs Gauge results. If the gauge isn't measuring from the same spot as the OBDII it can be off. If the gauge was not calibrated for altitude or air pressure changes it can be off. If the gauge was slammed in shipping it can be off. If the sensor the OBDII unit is using is wrong it can be off. This isn't a thread for my gauge is better than your gauge. This isn't a fan boy thread. I am more looking for tested numbers. Now horror stories are always good, and build quality is always good. If you have an AutoMeter and it has glass vs a ProSport plastic lens thats good to know. If your gauge is almost unreadable if sunlight hits it thats good to know. I have personally only ever run software or AutoMeter Gauges and they lasted a good 3 years per calibration.

So what kind of accuracy problems, and/or what kind of perfect accuracy are you seeing from your gauges? Make? Model? Size? Where is the gauge reading being taken at? Units of Measurement?

There are other options too if you are using something like DashCommand, Defi Advance Sport Club, Dash Hawk, or a car pc the input would be greatly appreciated.

Mazurfer

Have two PLX DM-200's.
One monitors the ODBII, so we won't talk about that one.
Other one take inputs from the PLX device oil pressure and oil temp senders off the RB oil adapter plate. I don't really care about calibration so much as I am looking for changes outside of what I have determined is my "baseline" on temp and pressure....although I did set the warnings up, so it will alert me if I miss it!

This concludes my participation as I know you are really looking for other things besides this.

DocBeech

iTrader: (1)

Well its a gauge whos accuracy depends on the accuracy of the cars OBDII sensors. The other would still apply if you know the accuracy of the gauge? How is it holding up? Do you feel it needs to be calibrated because now after "X" amount of time of owner ship its reading a little high or low?

Mazurfer

Oil temp = accuracy ~1 Deg C (~2 Deg F)
Oil Pressure = accuracy 1 PSI

Calibration, they only make a very benign statement.

http://www.plxdevices.com/Installati...UsersGuide.pdf
http://www.plxdevices.com/Installati...UsersGuide.pdf

http://www.plxdevices.com/support/PL...atalog2008.pdf

bse50

My cheap prosport gauges (water temp and oil temp) are within 2°C from the otherwise measured data. I can't talk about the oil pressure one since i don't have other tools to measure the pressure.
When i bought them they were a bit more off, a stronger negative connection solved the issue

olddragger

iTrader: (3)

I have ran autometer(mechanical and electrical, prosports, innovate wide band and cyberdine.
Accuratcy for all are acceptable. Prosports (dark lense) are more difficult to read in the daytime if mounted on the dash and not ashtray level. If I had to do over i would have gotten the clear lenses.
Also with the mazmart oil pressure regulator mod---on cold starts it pegs the 100psi reading on the gauge. I need a 140 max gauge I guess. Does fine after warming. Also identical readings to the autometer one I had before.
Some are very sensitive to the grounding points--prosports more so than the others.
OD

SleepeR1st

iTrader: (2)

I run a ScangaugeII with water temp, Intake air temp, blah blah, not too many super important features. No oil temperature though =/

For my 4 real time gauges i have fuel mileage, water temp, RPM, and actual MPH.

Obviously the RPM's are very off from the stock gauge, about 100RPM off per every 2,000RPM visual, increasing exponentially to 500RPM off at 9000. I'm assuming the water temperature gauge is accurate as i see the obvious fluctuation in temperature change/varying speed.

Fuel economy seems to be generous at a 3-5% above the actual overall fuel economy.
I have not calibrated the gauges nor do i know how to, it simply plugs into the OBDII port.

HiFlite999

iTrader: (2)

Not to be a PIA, but that is a linear, not exponential, increase.

HiFlite999

iTrader: (2)

So far, I've tried 4 different brands/types of gauges. Temperature calibrations were checked first with the gauge set on my kitchen counter, a 12 v power supply, the sender, a pot of hot water, and an accurate thermometer. If that checked ok, I put the gauge set in the car, ran the wires, and hooked up the sender with the wires run through the firewall, and dip tested the sender in boiling water. Some combinations of gauge-sender were pretty good, others pretty bad (like reading 195F in 212F water), as tested in the kitchen. Even the combos tested there that were good, could go very bad when installed in the car.

Rather than try to sort out the dozen or so scrap pieces of paper with calibrations on them, I'll share the lessons.

Everyone talks about the gauges (ahhh shiney!) and seldom mention the sending units. Generally, the worst are single-wire types where the body of the unit is supposed to serve as ground. What it does instead is set up giant ground loops that make it any sort of predictable preformance very iffy. Better are 2-wire kinds that make it easy to run a seperate ground wire to the guage cluster. Best are senders powered off an independent 5v power supply and read by a gauge capable of taking 0-5V inputs and having programmable calibrations. AEMelectronics has a good selection of 5v powered senders. Note that they provide a guaranteed-accurate calibration curve for each of the units they sell.

Unfortunately, most inexpensive gauge heads have a hard-wired calibration that cannot be changed. They are supposedly paired with senders that reflect this calibration, but I've found this not to be the case. If one has several senders lying around, don't be afraid to mix and match to find a combo that works best. I've found Glowshift to give reasonable results (+-3 degF @212F) though I did get one pretty bad sender - just replaced it with another one I had lying around.

I've also checked calibrations on the pressure combos I've tried, using a bunch of fittings and compressed air. Overall accuracy with them can be much worse than with the temp gauges, over 50% in some cases. Grounding is also a pain. Some are also pretty "sticky", and depend on engine vibration to help overcome friction of parts moving inside from the pressure changes.

DocBeech

iTrader: (1)

I have been talking with reps from a number of different companies. Here is what they told me:

ProSport stated they are calibrated to within 1% and use the most advanced stepper motors. They are actually almost the same build as Defi. The difference between the two is the sending units. Where defi uses an external computer ProSport uses an internal computer. As for whos is more accurate? They both claim the same accuracy.

Autometer responded that they are within industry standards(3%) but you can expect better results from them. They also told me they have the most heavy duty and trusted gauges on the market. So basically they were telling me the gauges would withstand the most abuse.

AEM doesn't have peak/warn on them, and also they only goto 1800deg on the exhaust temp, which worked great on a v8 just not so much on a rotary lol.

Mazurfer

Yep, the grounding is most important thing in almost every application.
The two wire senders(assuming electronic) are obviously better than the singles, but you need good strong grounds on them as well.
Also for the most part, you need to stay with the recommended sensors for whatever gauge you are running. They usually do test and spec them as a pair.

IronTanuki

Hopefully this isn't too far off topic but another company to look into is SPA. Their gauges are very configurable (units, seperate warning and error (yellow and red) LEDs per value, contrast, red or green backlight, optional high resolution sensor inputs, peak readouts, etc). You can also save space since each gauge functions as two completely different gauges with any combination of value readouts you could think of.

I have one of their oil temp and pressure gauges and it reads in tenths of a degree and seems fairly accurate on pressures as far as the FSM values and the temperature on cold start matches the outside temps. The only downside is they are a bit pricey and it took quite a while for them to fill my order but that was supposedly due to being back ordered on bezels.

DocBeech

iTrader: (1)

Here is the second reply I got from autometer. Originally I didn't specify so I figured well what if I asked about a specific line of products. Here is what they told me:

I had to check with an engineer for all of this and received this information back.

Since you listed Elite in the gauge selection, I'm assuming that's what you're referring to, so the following information is relevant to those.

-The accuracy of the gauges are ±1% of full scale reading (i.e. 1 PSI for a 100 PSI gauge & 1.5şF for a 100-250şF gauge).

-They were not tested side by side with other manufacturers

-They utilize a Stepper motor for sweeping.

-The temperature sensor is a Delphi transmission sensor. Pressure sensors are ratiometric 0.5 to 4.5V transducers.

-Yes, the temp gauges use brass.

-The lens is made out of Polycarbonate.

-All gauges read gauge pressure not absolute pressure, the pressure sensors automatically adjust to changes in barometric pressure, and the boost/vac gauge samples the atmospheric pressure and automatically adjusts to changes in pressure.

-All lab testing is done at Auto Meter; all gauges go through rigorous temperature, vibration, and noise immunity testing.

Gdawg522

Ok guys I have the same setup as Jedi, NYC Drift King, and Alz0rz with glowshift gauges. I have them all three setup with electronic senders. The senders have a signal wire and ground wire so there is no need to ground the sender itself with a clamp and wire. Regardless, I still did that not realizing it was unnecessary. You can refer to Jedi's thread here for details on what I did.

https://www.rx8club.com/showthread.p...light=nordskog

https://www.rx8club.com/showthread.p...ight=glowshift

Now the problem that I'm having is the gauge accuracy. The water temperature pickup is using the RB adapter at the heater hose return line near the washer fluid bottle. The oil plate houses my oil temp and pressure senders. I have all three senders and the three gauges grounded to the ground screw on the driver side right near the Master Cylinder bleed screw. The gauges seem to be off in their temperature but at the same time I'm not really sure. On the Cobb, my water temperature will read 180 and then at my gauge, the temp will read around 160. The water temp is usually around 20 degrees colder than the cobb states. I haven't verified the temperature at the heat hose where my sender it but I was thinking I could shoot the infrared thermometer at the RB block and get a general idea. If the block temperature is hotter than the gauge temp is reading, then I know I have a problem. The thing that confuses me is that both oil and water temps stay close to each other so I think the gauges are working correctly and they are grounded correctly. Let me know what you think I should do. I would really like for all my gauges to be as accurate as possible. Anyone with the same setup with glowshift gauges and electronic senders if you could chime in that would be great. Thanks

9krpmrx8

iTrader: (46)

I have an Auber Instruments oil temp gauge and Prosport Fuel and Oil Pressure. Grounding is important. Auber was very helpful in setting up my gauge and very helpful. They actually primarily work in the food service industry and make temp units for commercial grade cappuccino machines, etc.

At first I was having issues and I talked to the engineer and he walked me through how to properly ground the metal sheathing that surrounds the wires from the sending unit. Apparently it was picking up some type of interference that would cause the gauge to go into an error mode. The Auber gauges are calibrated to the thermo coupler that comes with it but he said they could be calibrated to work with others. But the Auber is not the prettiest gauge But I like it.

My Prosport oil pressure gauge has been very reliable and accurate before and after my Mazmart oil pressure mod. And the Prosport was the only one that read high enough, all the others only went to 100PSI. My Prosport Fuel pressure gauge is new so i cannot speak to it's accuracy but i will be reading fuel pressure from the Aeromotive Fuel line adapter. I will also be moving my oil temp to read from the pan and not the oil filter adapter this weekend.

DocBeech

iTrader: (1)

GDawg 522, you also need to remember where the readings are being taken. The stock temp sensor which is where your COBB gets its readings from is at the thermostat. You are taking the temps at the heater hose. A number of things can cause problems here so I will go over each of them. Typically you won't see the same reading from both the OBDII and the Custom Gauge but just in case:

The heater hose could be needing a cleaning. They do start to build up debris like any other hose, and there are threads on people getting black gunk out of the heater hose. First thing I would do if I was you is to remove this hose and clean it.

Either one of the senders could be off calibration. The stock OEM or the Aftermarket. I wouldnt be able to tell you which, you would need to test each of them individually. You will need an extremely accurate thermometer to test the aftermarket gauge. You can replace the sender in the car for about 30 bucks. They do start to read less and less accurate over time.

The spot you chose to ground might not be clean enough or free of interference. You put it right behind the gauge cluster next to the brake booster which also recieves intereference from the ABS. Go with a spot that is less prone to other electrical interference. Just like 9K stated, it has to be grounded properly. You can also buy wire shielding and electronic filters. The filters will ground out any body electrical interference.

Shooting the IR Therm won't help you. The sender is taking an internal temp and the plate is colder on the outside than on the inside. The sender will be in the direct flow of the fluid. Plus an IR Therm can be as much as +/- 4 deg. Some of the better ones are within +/- 2 deg. You would need to directly measure the temp of the coolant at the exact same location with a precision instrument.

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9K

Are you drilling to move the oil temp?

Or will you just risk the sender everytime you change the oil? :P
I know they make special oil pans with dual ports. They aren't cheap though.

Dirt_Nasty

iTrader: (2)

I had a similar stuation, if you have your gauges daisy chained and one of the gauges is messed up it will affect your others, unplug one temp wire and plug it into the back of another temp gauge, it should read the same, they are just different face plates.

9krpmrx8

iTrader: (46)

I am actually pulling oil temps from the oil drain pan bolt location. I use an oil extractor to change my oil so I don't use the drain plug. I will still take oil pressure from the oil filter adapter plate because I saw no pressure difference in the lower RPM when reading from the factory oil pressure sending unit location. My reading from the oil filter adapter plate seem to be on par with what others are seeing with the Mazmart oil pressure mod.

HiFlite999

iTrader: (2)

That's good to know, Thanks!

HiFlite999

iTrader: (2)

I also have Glowshift gauges. They were wildly inaccurate, plus being unstable with the engine running, until I ran the ground wire all the way back thru the firewall and connected it to the same ground wire the gauge set itself was using (cigar lighter). Try the following test: With the gauges installed in the car, unscrew the temp sender and dip it into boiling water right there under the hood. (I used an immersion heater to be sure the water was fully at 212 F.) The gauge should read very close to 212, though if you're picky or at high altitude you might compensate for the lower boiling point there. Even with the ground run back to the gauges, one was reading ~15 deg low. I took another sender I got from a different gauge set, replaced that one with it, and got a much better reading.

lgilbert50

iTrader: (1)

My experiences with water temp sender location, first had the sender at the RB (heater hose) location and my gauge (Prosport) read 15 to 20 degrees less the the obd. Then placed the sender in the radiator hose and got readings that matched the obd exactly. The only problem was that the gauge will not read until the thermostat opened usually after 5 minutes of running plus if the thermostat sticks closed you have no warning of overheating until the engine goes south. Wondering if anyone tried the drain bolt on the block for the sender location seems like it would be the ideal location if an adapter can found or made.
Just my 2 cents

06 Shinka

HiFlite999

iTrader: (2)

BTW, I now take my OT reading from a banjo bolt in the oil line from the engine going to the LHS oil cooler. Not only does it read considerably warmer than that taken from the sandwich plate, response to changing engine conditions is very fast.

HiFlite999

iTrader: (2)

Depends what one wishes to accomplish. If you with to "duplicate" the OBDII reading, then the upper radiator hose or perhaps the drain bolt as you mentions. I display the OBDII reading on the LED using a Goodbox. My add-on gauge is looking at the *lower* radiator hose which gives the temp of water coming from the radiator. This will stay at a pretty constant 165 F if the thermostat is not completely open. Under thermal stress, the thermostat goes fully open and the feed water to the engine starts getting hotter. Above ~173 F, the OBDII will start rising above 180 F.

lgilbert50

iTrader: (1)

Going over the Mazda heater parts diagram I realized that the hose that the RB adapter is on the return line from the heater core, the coolant has to past the heater core which is a small radiator hence cooler temps (my 15 to 20 degrees drop and from other posts (Gdawg522) with the same problem) then the engine temp. It makes more sense to me to mount it on the feed line just below the return line, the coolant then comes directly from the engine and closer to the real temp. I'm welcome to anyone to point out any errors in my thinking before I start cutting up expensive hoses.

06 Shinka

HwAoRrDk

When I was putting together my GOODbox setup, I chose some sensors/senders from AeroForce Technology that came with a specific calibration curve.

For example, from the documentation that came with their fluid temperature sensor:



Although, even with this I still don't get 100% accuracy with my GOODbox's oil temperature readout because it can only convert the sensor input to temperature on a linear basis (which is represented on their graph by the red line). As a result, it reads a little bit under at low temps and a little over at higher temperatures.