diff --git a/include/net/ppp.h b/include/net/ppp.h
index c5f307a4b66..fb1c1ca400a 100644
--- a/include/net/ppp.h
+++ b/include/net/ppp.h
@@ -611,7 +611,8 @@ static inline void ppp_mgmt_raise_carrier_off_event(struct net_if *iface)
  * @brief Send PPP Echo-Request to peer. We expect to receive Echo-Reply back.
  *
  * @param idx PPP network interface index
- * @param timeout Amount of time to wait Echo-Reply.
+ * @param timeout Amount of time to wait Echo-Reply. The value is in
+ * milliseconds.
  *
  * @return 0 if Echo-Reply was received, < 0 if there is a timeout or network
  * index is not a valid PPP network index.
diff --git a/subsys/net/ip/net_shell.c b/subsys/net/ip/net_shell.c
index 87b888dc965..755fcd49736 100644
--- a/subsys/net/ip/net_shell.c
+++ b/subsys/net/ip/net_shell.c
@@ -3213,7 +3213,7 @@ static int cmd_net_ppp_ping(const struct shell *shell, size_t argc,
 			return -ENOEXEC;
 		}
 
-		ret = net_ppp_ping(idx, K_SECONDS(1));
+		ret = net_ppp_ping(idx, MSEC_PER_SEC * 1);
 		if (ret < 0) {
 			if (ret == -EAGAIN) {
 				PR_INFO("PPP Echo-Req timeout.\n");
diff --git a/subsys/net/l2/ppp/fsm.c b/subsys/net/l2/ppp/fsm.c
index 06d2d3ec773..743ce0f9681 100644
--- a/subsys/net/l2/ppp/fsm.c
+++ b/subsys/net/l2/ppp/fsm.c
@@ -19,7 +19,7 @@ LOG_MODULE_DECLARE(net_l2_ppp, CONFIG_NET_L2_PPP_LOG_LEVEL);
 #define BUF_ALLOC_TIMEOUT K_MSEC(100)
 
 /* This timeout is in milliseconds */
-#define FSM_TIMEOUT CONFIG_NET_L2_PPP_TIMEOUT
+#define FSM_TIMEOUT K_MSEC(CONFIG_NET_L2_PPP_TIMEOUT)
 
 #define MAX_NACK_LOOPS CONFIG_NET_L2_PPP_MAX_NACK_LOOPS
 
@@ -118,8 +118,7 @@ static void ppp_fsm_timeout(struct k_work *work)
 
 			fsm->retransmits--;
 
-			(void)k_delayed_work_submit(&fsm->timer,
-						    FSM_TIMEOUT);
+			(void)k_delayed_work_submit(&fsm->timer, FSM_TIMEOUT);
 		}
 
 		break;
@@ -517,7 +516,7 @@ int ppp_send_pkt(struct ppp_fsm *fsm, struct net_if *iface,
 		 * in that case.
 		 */
 		(void)k_delayed_work_submit(&fsm->sender.work,
-				IS_ENABLED(CONFIG_NET_TEST) ? K_MSEC(1) : 0);
+			  IS_ENABLED(CONFIG_NET_TEST) ? K_MSEC(1) : K_NO_WAIT);
 	} else {
 		ret = net_send_data(pkt);
 		if (ret < 0) {
diff --git a/subsys/net/l2/ppp/ppp_l2.c b/subsys/net/l2/ppp/ppp_l2.c
index c5d4dc07e12..131746c4f0a 100644
--- a/subsys/net/l2/ppp/ppp_l2.c
+++ b/subsys/net/l2/ppp/ppp_l2.c
@@ -373,7 +373,7 @@ int net_ppp_ping(int idx, s32_t timeout)
 		return ret;
 	}
 
-	ret = k_sem_take(&ctx->shell.wait_echo_reply, timeout);
+	ret = k_sem_take(&ctx->shell.wait_echo_reply, K_MSEC(timeout));
 
 	ctx->shell.echo_reply.cb = NULL;