diff --git a/java_console/io/src/main/java/com/rusefi/io/serial/RateCounter.java b/java_console/io/src/main/java/com/rusefi/io/serial/RateCounter.java
index 51c9594811..8fad5a926c 100644
--- a/java_console/io/src/main/java/com/rusefi/io/serial/RateCounter.java
+++ b/java_console/io/src/main/java/com/rusefi/io/serial/RateCounter.java
@@ -5,6 +5,7 @@ import com.rusefi.Timeouts;
 import java.util.LinkedList;
 
 public class RateCounter {
+    private final static int MAGIC_DURATION = Timeouts.SECOND;
 
     private final LinkedList<Pair> timeStamps = new LinkedList<>();
 
@@ -16,7 +17,7 @@ public class RateCounter {
     }
 
     public synchronized int getCurrentRate(long now) {
-        long threshold = now - Timeouts.SECOND;
+        long threshold = now - MAGIC_DURATION;
 
         while (!timeStamps.isEmpty() && timeStamps.peekFirst().timestamp < threshold)
             timeStamps.removeFirst();
@@ -27,12 +28,16 @@ public class RateCounter {
         return result;
     }
 
+    public synchronized int getSizeForUnitTest() {
+        return timeStamps.size();
+    }
+
     public void add() {
         add(System.currentTimeMillis());
     }
 
-    public synchronized void add(long now) {
-        timeStamps.add(new Pair(now, 1));
+    public synchronized void add(long timestamp) {
+        timeStamps.add(new Pair(timestamp, 1));
     }
 
     private static class Pair {
diff --git a/java_console/io/src/main/java/com/rusefi/io/stream/PCanIoStream.java b/java_console/io/src/main/java/com/rusefi/io/stream/PCanIoStream.java
index 041f41bf1c..328fa5d7c0 100644
--- a/java_console/io/src/main/java/com/rusefi/io/stream/PCanIoStream.java
+++ b/java_console/io/src/main/java/com/rusefi/io/stream/PCanIoStream.java
@@ -8,6 +8,7 @@ import com.rusefi.io.IoStream;
 import com.rusefi.io.can.IsoTpCanDecoder;
 import com.rusefi.io.can.IsoTpConnector;
 import com.rusefi.io.serial.AbstractIoStream;
+import com.rusefi.io.serial.RateCounter;
 import com.rusefi.io.tcp.BinaryProtocolServer;
 import com.rusefi.ui.StatusConsumer;
 import org.jetbrains.annotations.Nullable;
@@ -28,6 +29,9 @@ public class PCanIoStream extends AbstractIoStream {
     private final IncomingDataBuffer dataBuffer = createDataBuffer("[PCAN] ");
     private final PCANBasic can;
     private final StatusConsumer statusListener;
+
+    private final RateCounter totalCounter = new RateCounter();
+    private final RateCounter isoTpCounter = new RateCounter();
     private final IsoTpCanDecoder canDecoder = new IsoTpCanDecoder() {
         @Override
         protected void onTpFirstFrame() {
@@ -109,13 +113,16 @@ public class PCanIoStream extends AbstractIoStream {
         TPCANMsg rx = new TPCANMsg(Byte.MAX_VALUE);
         TPCANStatus status = can.Read(CHANNEL, rx, null);
         if (status == TPCANStatus.PCAN_ERROR_OK) {
+            totalCounter.add();
             if (log.debugEnabled())
                 log.debug("Got [" + rx + "] id=" + String.format("%X", rx.getID()) + " len=" + rx.getLength() + ": " + IoStream.printByteArray(rx.getData()));
             if (rx.getID() != CAN_ECU_SERIAL_TX_ID) {
 //                if (log.debugEnabled())
                 log.info("Skipping non " + String.format("%X", CAN_ECU_SERIAL_TX_ID) + " packet: " + String.format("%X", rx.getID()));
+                log.info("Total rate " + totalCounter.getCurrentRate() + ", isotp rate " + isoTpCounter.getCurrentRate());
                 return;
             }
+            isoTpCounter.add();
             byte[] decode = canDecoder.decodePacket(rx.getData());
             listener.onDataArrived(decode);
 
diff --git a/java_console/io/src/test/java/com/rusefi/io/serial/RateCounterTest.java b/java_console/io/src/test/java/com/rusefi/io/serial/RateCounterTest.java
index 671cf49768..81bc527888 100644
--- a/java_console/io/src/test/java/com/rusefi/io/serial/RateCounterTest.java
+++ b/java_console/io/src/test/java/com/rusefi/io/serial/RateCounterTest.java
@@ -13,15 +13,19 @@ public class RateCounterTest {
 
         assertEquals(0, rateCounter.getCurrentRate());
 
-        rateCounter.add(1);
+        rateCounter.add(/*timestamp*/1);
         rateCounter.add(1);
         rateCounter.add(1);
         rateCounter.add(1);
 
+        // cute size effect: FUTURE timestamps are also counted :)
         assertEquals(4, rateCounter.getCurrentRate(0));
+        assertEquals(3, rateCounter.getSizeForUnitTest());
 
 
         assertEquals(0, rateCounter.getCurrentRate(2 * Timeouts.SECOND));
+        // assert purge of oldest records
+        assertEquals(0, rateCounter.getSizeForUnitTest());
     }
 }