Per-Cylinder EGT Gauge with the Haltech TCA-8

Exhaust gas temperature is the closest thing you have to looking inside each cylinder. A single EGT probe tells you how hot the engine is running overall; one probe per cylinder shows you which cylinder is running leaner or hotter than the rest — often the first sign of a fuelling, ignition or injector problem. The Haltech TCA-8 reads up to eight thermocouples, and a KrispyGauge puts those temperatures on your dash.

Why per-cylinder EGT

• Protect the engine. Excessive exhaust temperature cooks turbochargers, valves and pistons. A warning on the dash lets you back off before damage is done.
• Balance the tune. Differences between cylinders point straight at the injector, coil or runner that needs attention.
• Turbo and diesel engines especially benefit — EGT is often the limiting factor on how hard they can be pushed.

What you need

• A Haltech TCA thermocouple amplifier — the TCA-8 handles eight channels: one probe per cylinder on anything up to a V8.
• K-type thermocouple probes, one per channel, fitted in the exhaust manifold or headers.
• A KrispyGauge on the same CAN bus.

Works alongside your ECU

KrispyGauge reads the TCA directly over CAN. It sits on the same bus as your ECU, adding EGT channels without taking anything away — the gauge keeps showing everything else from the ECU as well.

KrispyGauge also supports the smaller TCA-2 and TCA-4, and the AEM 30-2224 eight-channel thermocouple module (in beta).

Setting it up

1. Fit the probes and wire them to the TCA, then connect the TCA to power and to the CAN bus with the KrispyGauge.
2. Join the gauge's WiFi network (Krispy_XXXX, password GetKrispy) and open http://4.3.2.1.
3. Under Settings, choose your TCA — TCA-8, a TCA-4 box A or B, or a TCA-2 — and set the CAN bus speed to 1 Mbit/s.
4. Under Page Config, put the EGT channels you want on your gauge pages: EGT 1 to EGT 8, in °C.

The full list is on the Haltech TCA supported signals page, and connection details are in the Web UI guide.

Set an EGT warning

Give each EGT page a warning threshold below the temperature your engine builder or turbo manufacturer recommends. If a cylinder goes over, the gauge flashes a full-screen alert you can't miss.

Common questions

Can I use it without a Haltech ECU?

Yes. KrispyGauge reads the TCA directly, so it works alongside any supported ECU — or with no ECU on the bus at all.

How many EGT channels can I show?

All eight from a TCA-8. Choose which channels go on which gauge page in the Web UI.

Where should the probes go?

As close to the exhaust port as practical, at the same distance on every runner, so the readings compare like for like.