What a trace display is
A trace display draws a rolling graph of one or more ECU channels over time, a bit like a live mini data log sitting on your ESP screen. It's the best way to watch anything that moves quickly or that you need to see in relation to something else: a wideband reading following a throttle blip, boost against its target, idle speed wandering, or a sensor that drops out for a split second.
Using it
- Up to five channels can share one trace display.
- Focus: the display's name and axis values belong to one channel at a time. Click a channel's name inside the display to bring it into focus, and the scale switches to that channel.
- Pause and resume: the play/pause button in the top right corner freezes that trace so you can study what just happened. Click it again to carry on. Pausing one trace doesn't stop the others or the ECU.
- Add or remove channels: right-click the display.
Properties
Right-clicking also opens the display's properties, where you can set:
| Setting | What it does | Our advice |
|---|---|---|
| Channel color | The line color for each channel | Pick colors with strong contrast so overlapping lines stay readable |
| Time span | How many seconds of history are shown | Short for fast events like transient fueling, longer for idle or temperature trends |
| Maximum value | The top of the displayed scale | Set it just above the highest value you expect, so small changes aren't squashed flat |
| Units | The units shown for the channel | Match what you use everywhere else to avoid mental conversions mid-tune |
How we use trace displays
We keep a few traces on our standard tuning layouts:
- Air/fuel ratio with throttle position, to see lean or rich spikes when the throttle moves and dial in transient fueling.
- Boost with boost target, to spot overshoot and oscillation in boost control.
- RPM with idle target, to check idle control settles without hunting.
- Injector pressure differential, to confirm fuel supply holds steady under load.
When something looks odd, pause the trace straight away before the event scrolls off the screen, then click through each channel to read its values. For anything longer than a few seconds, a proper data log is the better tool.
Other display types include the dial gauge, bar gauge and text view. You can also watch tables in the 2D view and 3D view.
