diff --git a/Software/src/can_obd2.cpp b/Software/src/can_obd2.cpp
index b40f3ae..a2b9ce3 100644
--- a/Software/src/can_obd2.cpp
+++ b/Software/src/can_obd2.cpp
@@ -3,7 +3,7 @@
 #include "dtc.h"
 #include "debugger.h"
 #include "globals.h" 
-#include <stdarg.h>
+#include <stdio.h>
 
 // Trace-Sink aus webui.cpp (o.ä.)
 extern void TRACE_OnObdFrame(uint32_t id, bool rx, const uint8_t *d, uint8_t dlc, const char *note);
@@ -72,8 +72,6 @@ static uint32_t s_lastRespTime = 0;
 static uint32_t s_lastIntegrateMs = 0;
 static uint32_t s_lastSpeedMMps = 0;
 
-static uint32_t s_lastDbgMs = 0;
-
 // =======================
 // Hilfsfunktionen
 // =======================
@@ -87,22 +85,6 @@ static inline uint32_t kmh_to_mmps(uint16_t kmh)
   return (uint32_t)kmh * 1000000UL / 3600UL;
 }
 
-static inline void maybeDebug(uint32_t now, const char *fmt, ...)
-{
-#if 1
-  if (now - s_lastDbgMs < OBD2_DEBUG_INTERVAL_MS)
-    return;
-  s_lastDbgMs = now;
-  va_list ap;
-  va_start(ap, fmt);
-  Debug_pushMessage(fmt, ap); // nimmt va_list
-  va_end(ap);
-#else
-  (void)now;
-  (void)fmt;
-#endif
-}
-
 // =======================
 // Öffentliche API
 // =======================
@@ -155,7 +137,6 @@ bool Init_CAN_OBD2()
   s_lastRespTime = 0;
   s_lastIntegrateMs = now;
   s_lastSpeedMMps = 0;
-  s_lastDbgMs = 0;
 
   Debug_pushMessage("CAN(OBD2): Filters set (7E8..7EF), NORMAL mode\n");
   return true;
@@ -198,7 +179,12 @@ uint32_t Process_CAN_OBD2_Speed()
       {
         // Senden fehlgeschlagen -> harter Timeout-DTC
         MaintainDTC(DTC_OBD2_CAN_TIMEOUT, true);
-        maybeDebug(now, "OBD2-CAN send failed (%u)\n", st);
+        static uint8_t dbgSendFail = 0;
+        if (++dbgSendFail >= 10)
+        {
+          dbgSendFail = 0;
+          Debug_pushMessage("OBD2-CAN send failed (%u)\n", st);
+        }
       }
     }
   }
@@ -253,8 +239,13 @@ uint32_t Process_CAN_OBD2_Speed()
       snprintf(note, sizeof(note), "speed=%ukmh", (unsigned)speedKmh);
       TRACE_OnObdFrame(rxId, /*rx=*/true, rx, len, note);
 
-      maybeDebug(now, "OBD2 speed: %u km/h (%lu mm/s)\n",
-                 (unsigned)speedKmh, (unsigned long)s_lastSpeedMMps);
+      static uint8_t dbgSpeed = 0;
+      if (++dbgSpeed >= 10)
+      {
+        dbgSpeed = 0;
+        Debug_pushMessage("OBD2 speed: %u km/h (%lu mm/s)\n",
+                          (unsigned)speedKmh, (unsigned long)s_lastSpeedMMps);
+      }
       break; // eine valide Antwort pro Zyklus reicht
     }
     else