When you are having issues with your gauge there may be a simple fix. Here we’ll go over some common symptoms and ways to diagnose the issue. It’s not common for parts to fail or to be defective out of the box as we do thorough testing prior to shipping are products. Sometimes something very simple can get overlooked during installation so take a few minutes to look over this page for some help. We recommend 16g - 22g wiring for your installation.
Lets start with some common gauges issues that could happen with any gauge.
Performance / Digital / EVO series gauges:
Red and White wires can be together on one accessory source.
Everything wired correctly but the gauge wont power on? Check the harness connection at the back of the gauge. The plastic clip surrounding the pins can sometimes get pulled up off of the circuit board causing the pins to be shortened so when you plug in your harness the pins can’t contact the wires in the harness. This can happen if the harness is plugged in and gets yanked on before releasing the locking clip. Try pushing down on the harness seat surrounding the pins on the gauge with a flathead screw driver so it makes contact with the circuit board. Using about 10-15lbs of pressure should force the clip down.
Premium / Halo / JDM / Premium EVO series gauges:
Premium series gauge button stuck? https://youtu.be/D3GjdSTW8Lw
The gauge is just blinking or showing “- - -“ This is probably the most common installation issue. The sensor harness has a 2-stage locking mechanism. It is really hard to successfully push that harness into it’s connector with just your fingers. It may feel like it’s in all the way and it isn’t pulling out easily with a tug so you assume it’s in all the way. Try taking a flat head screw driver to the sensor harness clip while plugged in. Give it about 10-15lbs of pressure to ensure it’s plugged in all the way. You may even notice the click sound of the locking mechanism.
Gauge works fine but every time I restart the vehicle my settings reset. This means your red power wire isn’t on a constant 12v power source. Meaning even when the vehicle is off the red wire is still receiving 12v of power. This is the memory wire just like in your radio to save your stations. You’ll want to find a fused power source using a test light or a multi tester that shows 12v even with the key out of the ignition.
Gauge sitting at the top or botton of the scale? Possibly even blinking? The goal here is to have the gauge sitting at 0 with your key switched to the “ON” position and your engine off. If it’s sitting at 0 that’s a good sign everything is wired up correctly.
Gauge sits at 0 even with the engine on? Check your vacuum line. More than likely you are on a bad intake manifold vacuum source or possibly a leak in one of the hoses. To confirm your vacuum source is good, check for suction by placing your finger on the vacuum line coming out of your intake with the engine on.
Gauge sitting at a negative number with your key on / engine off? You’re probably at a higher altitude and the electronic boost sensor is affected by atmospheric pressure. So, using the supplied white pick tool in the gauge packaging box or a 2mm hex wrench you can calibrate the gauge from the back. You’ll see a hole at the 3’oclock or 9’oclock position. If there are two holes, one is for brightness. Just turn the key to the “ON” position and adjust the gauge until it sits at 0. If you can’t get it to 0, you’re at too high of an altitude and we recommend a mechanical boost gauge.
Gauge not getting any readings - You can check your sensor with a multi tester to confirm if it’s a connection issue or a defective sensor. With the key on / engine off, probe the red and black wires to confirm the sensor is getting power. If the sensor plugs directly into the gauge, its should be getting 5v. If the sensor powers separately, it should be 12v. If you confirm the sensor is getting power, check the white wire. It should be showing 1v. (Signal wire. 1v=0 psi) If its not, the sensor is bad. If it is, check the green wire at the back of the gauge for 1v (or white sensor harness wire for premium gauges) to confirm the connection is good all the way up to the gauge.
Oil pressure gauge
Performance series (Gold sensor w/ two twist on terminals):
If the gauge does the start up opening ceremony (needle back and forth) then comes to a rest and sits at the top of the scale, it’s either a bad connection to the sensor or the sensor is bad. A quick check for these sensors is to use a multi tester to check the resistance across the two terminals. You should be getting about 3 ohms with no power on in the vehicle. If you’re getting OL or the numbers are way off then the sensor is bad. If you are getting 3 ohms, confirm that your green wire at the back of the gauge is also getting 3 ohms. You can remove the harness and probe inside of the clip to confirm this. This will verify if it’s the connection from the sensor signal to the gauge is good.
Premium series (small, silver and black, single 3 wire plug)
If the gauge is sitting at 0 and blinking white on and off That means there’s a connection issue to the sensor or the sensor is defective. To check if the sensor is defective you’ll want to verify that the sensor is getting 5v at the red power wire on the sensor by probing with a multi tester. This can be done with the key on / engine off. Then you’ll check for .5v at the white wire. If you’re getting .5v (0 psi) turn on the engine and check for around 1v-1.2v. (15-20 psi). If you’re getting power to the red wire and nothing from the white, then it’s a bad sensor.
Wideband Air fuel ratio gauge:
Changing the default color of your EVO series Red.Blue or Green/White wideband: https://youtu.be/8eVGqZuh4Y8
Gauge sitting at or displaying 10? This is the most common installation issue for this gauge. Unlike any of our other gauges, this gauge MUST have the white wire connected to a 12v accessory source. This is the heater wire for the o2 sensor. On other gauges, it’s an optional color wire. If you connect it to a 12v and you start getting a reading but you find that the colors are opposite of what you want, you will switch pins 2 and 4 on ONE side of the gauge to box harness. You can do this with a pick or pen. You’ll see some exposed metal on the end of the harness clip with numbers below. Push down on the metal and pull on the wire to release it from the clip.
Gauge reading 20 randomly or all of the time? Check the connections to the o2 sensor. If everything is good there, the o2 sensor is defective. The o2 sensor can go bad if it’s getting too hot. Make sure to install it at least 3 feet away from the motor.
On the gauge / sensor harness, Pink to white sensor wire and blue to black sensor wire.
Not all gauges are listed in this troubleshooting guide because they can be diagnosed from the first section with general connection issues. See below sensor voltage and resistance references.
Gauge pointer is erratic , kind of works at low RPMS? Your car has a distributor right? Basically anything pre 1999 will need a "12v square wave tach converter" The part we recommend for most vehicles is MSD 8132 which can be purchased from other online sites. Maybe local.. Do your research for the model number required for your specific application. The converter converts that AC signal to 12v square wave which is what most modern tachometers require.
Ford Mustangs require a tach converter from 1964-2017
SensorsOur threaded sensors have a pipe threading on them. Here are some specs for correctly installing them.
NPT Fitting Assembly
NPT Size: 1/8
Turns Past Finger-Tight 1.5 to 3
**Approximate Torque: 12 ft-lb
** Torque values are given for reference only. Never use a torque wrench to tighten NPT fittings! Don't forget a couple layers of teflon tape on the threads