diff --git a/libraries/AP_ADC/AP_ADC_ADS7844.cpp b/libraries/AP_ADC/AP_ADC_ADS7844.cpp
index c3cf71cda2..96e3751d23 100644
--- a/libraries/AP_ADC/AP_ADC_ADS7844.cpp
+++ b/libraries/AP_ADC/AP_ADC_ADS7844.cpp
@@ -116,7 +116,6 @@ void AP_ADC_ADS7844::read(uint32_t tnow)
 			// reader below could get a division by zero
 			_sum[ch] = 0;
 			_count[ch] = 1;
-			last_ch6_micros = tnow;
 		}
 		_sum[ch] += (v >> 3);
 	}