diff --git a/firmware/controllers/math/closed_loop_fuel.cpp b/firmware/controllers/math/closed_loop_fuel.cpp
index 4276d0473b..8349036ba4 100644
--- a/firmware/controllers/math/closed_loop_fuel.cpp
+++ b/firmware/controllers/math/closed_loop_fuel.cpp
@@ -66,13 +66,13 @@ static bool shouldCorrect(DECLARE_ENGINE_PARAMETER_SIGNATURE) {
 	return true;
 }
 
-static bool shouldUpdateCorrection(DECLARE_ENGINE_PARAMETER_SIGNATURE) {
+bool shouldUpdateCorrection(DECLARE_ENGINE_PARAMETER_SIGNATURE) {
 	const auto& cfg = CONFIG(stft);
 
 	// Pause (but don't reset) correction if the AFR is off scale.
 	// It's probably a transient and poorly tuned transient correction
-	auto afr = Sensor::get(SensorType::Lambda);
-	if (!afr || afr.value_or(0) < (cfg.minAfr * 0.1f) || afr.value_or(0) > (cfg.maxAfr * 0.1f)) {
+	auto afr = Sensor::get(SensorType::Lambda).value_or(0) * 14.7f;
+	if (!afr || afr < (cfg.minAfr * 0.1f) || afr > (cfg.maxAfr * 0.1f)) {
 		return false;
 	}
 
diff --git a/firmware/controllers/math/closed_loop_fuel.h b/firmware/controllers/math/closed_loop_fuel.h
index aff0d2c426..efe894f9fc 100644
--- a/firmware/controllers/math/closed_loop_fuel.h
+++ b/firmware/controllers/math/closed_loop_fuel.h
@@ -5,3 +5,4 @@
 
 float fuelClosedLoopCorrection(DECLARE_ENGINE_PARAMETER_SIGNATURE);
 size_t computeStftBin(int rpm, float load, stft_s& cfg);
+bool shouldUpdateCorrection(DECLARE_ENGINE_PARAMETER_SIGNATURE);
diff --git a/unit_tests/tests/test_stft.cpp b/unit_tests/tests/test_stft.cpp
index 0f442bde64..f9237fa0d1 100644
--- a/unit_tests/tests/test_stft.cpp
+++ b/unit_tests/tests/test_stft.cpp
@@ -1,4 +1,5 @@
 
+#include "engine_test_helper.h"
 #include "closed_loop_fuel_cell.h"
 #include "closed_loop_fuel.h"
 
@@ -79,3 +80,19 @@ TEST(ClosedLoopFuel, CellSelection) {
 	EXPECT_EQ(3, computeStftBin(4000, 50, cfg));
 	EXPECT_EQ(3, computeStftBin(10000, 50, cfg));
 }
+
+TEST(ClosedLoopFuel, afrLimits) {
+	WITH_ENGINE_TEST_HELPER(TEST_ENGINE);
+
+	engineConfiguration->stft.minAfr = 100;  // 10.0 AFR
+	engineConfiguration->stft.maxAfr = 180;  // 18.0 AFR
+
+	Sensor::setMockValue(SensorType::Lambda, 0.1f);
+	EXPECT_FALSE(shouldUpdateCorrection(PASS_ENGINE_PARAMETER_SIGNATURE));
+
+	Sensor::setMockValue(SensorType::Lambda, 1.0f);
+	EXPECT_TRUE(shouldUpdateCorrection(PASS_ENGINE_PARAMETER_SIGNATURE));
+
+	Sensor::setMockValue(SensorType::Lambda, 2.0f);
+	EXPECT_FALSE(shouldUpdateCorrection(PASS_ENGINE_PARAMETER_SIGNATURE));
+}