Discussion and questions related to the course Link G4 Software Tutorial
Hi, first time poster.
Recently installed a Link Thunder on my Subaru Liberty GT I already owned an Innovate ECF-1, 4 in 1 gauge with Fuel Pressure, Ethanol %, Fuel Temperature and AFR. I've connected the 0-5v analog outputs of the gauge to analog inputs on the Thunder and labeled them respectively. I've used the calibration data provided with the Innovate gauge but the readings in PC Link don't match what is displayed on the gauge.
Fuel pressure is displayed on the gauge at 35psi with car off but reads 39psi in PC Link.
Ethanol % is 0.5% on the gauge and 3% in PC Link.
Fuel Temp is about 5 degrees higher in PC Link, the fuel is about ambient temperature.
So they all read higher in PC Link when compared to the gauge, the car does run but the AFR's are a bit erratic. I'm using the Innovate wideband controller with an analog input instead of the Thunder's on board wideband controller.
I'm not sure what could be causing this, any assistance would be great.
Sounds like a ground offset issue. The ground level the link is comparing those input signals to is slightly different to the ground level the innovate unit is using as a reference to generate them from, so the readings are a bit off. Two things you can do to help with this are to ground your Innovate unit to the same spot your Thunder is grounded to, and tweak the calibrations in the thunder till they match what the gauge is showing.
You will 100% want to wire your wideband directly to the controller in the thunder. The controller that is built into the thunder is far superior to the controllers in the innovate products, and having the gauge control the sensor and get the value, and then transmit this to the thunder via and analogue input is really a pretty big compromise.
If you've got enough spare inputs on your thunder, I'd wire all those sensors directly to the thunder itself and remove the innovate unit from the setup completely.
Thanks for your response Zac,
The Thunder has multiple earth wires which go to the engine bay. The innovate unit is earthed somewhere under the dash of the car, I'll try this first. I had a feeling it might be better to use the onboard wideband controller. As for the other sensors I'll see how I go, I may end up removing the Innovate gauge altogether and using a digital dash.
Yeah man, the Thunder is a pretty damn sexy ECU and you may as well use it to its fullest :-).
Did some troubleshooting, tried earthing the gauge in different locations. Didn't seem to change the value much, I'll probably connect the rest of the sensors directly to the ECU. Went to connect my LSU4.9 sensor to the ecu and found I only have 5 wires going to the sensor. Pin 5 is blanked off on the back of the connector. Pin 5 should be a green wire, which would connect to the MES input on the Thunder. Do I need a 6 wire version of the LSU4.9 or will the MES input not matter? Thanks again
No, the LSU4.9 will only have 5 wires heading to the sensor itself, but the connector will still have 6 pins, and you will need to wire pin 5 to the MES pin on the thunder. This pin connects to the calibration resistor inside the connector body of the LSU4.9, and the ECU uses it to determine the calibration of the o2 sensor. As you've discovered, there isn't a corresponding wire that head down from the connector body to the sensor body itself though :-).