diff --git a/apis/v1alpha1/opentelemetrycollector_webhook.go b/apis/v1alpha1/opentelemetrycollector_webhook.go
index 12b6d98904..8e7bd7c802 100644
--- a/apis/v1alpha1/opentelemetrycollector_webhook.go
+++ b/apis/v1alpha1/opentelemetrycollector_webhook.go
@@ -133,7 +133,7 @@ func (r *OpenTelemetryCollector) validateCRDSpec() error {
 
 	// validate autoscale with horizontal pod autoscaler
 	if r.Spec.MaxReplicas != nil {
-		if *r.Spec.MaxReplicas < int32(1) {
+		if *r.Spec.MaxReplicas <= int32(1) {
 			return fmt.Errorf("the OpenTelemetry Spec autoscale configuration is incorrect, maxReplicas should be defined and more than one")
 		}
 
@@ -150,11 +150,13 @@ func (r *OpenTelemetryCollector) validateCRDSpec() error {
 		}
 
 		if r.Spec.Autoscaler != nil && r.Spec.Autoscaler.Behavior != nil {
-			if r.Spec.Autoscaler.Behavior.ScaleDown != nil && *r.Spec.Autoscaler.Behavior.ScaleDown.StabilizationWindowSeconds < int32(1) {
+			if r.Spec.Autoscaler.Behavior.ScaleDown != nil && r.Spec.Autoscaler.Behavior.ScaleDown.StabilizationWindowSeconds != nil &&
+				*r.Spec.Autoscaler.Behavior.ScaleDown.StabilizationWindowSeconds < int32(1) {
 				return fmt.Errorf("the OpenTelemetry Spec autoscale configuration is incorrect, scaleDown should be one or more")
 			}
 
-			if r.Spec.Autoscaler.Behavior.ScaleUp != nil && *r.Spec.Autoscaler.Behavior.ScaleUp.StabilizationWindowSeconds < int32(1) {
+			if r.Spec.Autoscaler.Behavior.ScaleUp != nil && r.Spec.Autoscaler.Behavior.ScaleUp.StabilizationWindowSeconds != nil &&
+				*r.Spec.Autoscaler.Behavior.ScaleUp.StabilizationWindowSeconds < int32(1) {
 				return fmt.Errorf("the OpenTelemetry Spec autoscale configuration is incorrect, scaleUp should be one or more")
 			}
 		}
diff --git a/apis/v1alpha1/opentelemetrycollector_webhook_test.go b/apis/v1alpha1/opentelemetrycollector_webhook_test.go
index 39dc709551..a0d5b12bf4 100644
--- a/apis/v1alpha1/opentelemetrycollector_webhook_test.go
+++ b/apis/v1alpha1/opentelemetrycollector_webhook_test.go
@@ -18,6 +18,8 @@ import (
 	"testing"
 
 	"github.com/stretchr/testify/assert"
+	autoscalingv2 "k8s.io/api/autoscaling/v2"
+	v1 "k8s.io/api/core/v1"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 )
 
@@ -76,3 +78,255 @@ func TestOTELColDefaultingWebhook(t *testing.T) {
 		})
 	}
 }
+
+func TestOTELColValidatingWebhook(t *testing.T) {
+	zero := int32(0)
+	one := int32(1)
+	three := int32(3)
+	five := int32(5)
+
+	tests := []struct {
+		name        string
+		otelcol     OpenTelemetryCollector
+		expectedErr string
+	}{
+		{
+			name:    "valid empty spec",
+			otelcol: OpenTelemetryCollector{},
+		},
+		{
+			name: "valid full spec",
+			otelcol: OpenTelemetryCollector{
+				Spec: OpenTelemetryCollectorSpec{
+					Mode:            ModeStatefulSet,
+					MinReplicas:     &one,
+					Replicas:        &three,
+					MaxReplicas:     &five,
+					UpgradeStrategy: "adhoc",
+					TargetAllocator: OpenTelemetryTargetAllocator{
+						Enabled: true,
+					},
+					Config: `receivers:
+  examplereceiver:
+    endpoint: "0.0.0.0:12345"
+  examplereceiver/settings:
+    endpoint: "0.0.0.0:12346"
+  prometheus:
+    config:
+      scrape_config:
+        job_name: otel-collector
+        scrape_interval: 10s
+  jaeger/custom:
+    protocols:
+      thrift_http:
+        endpoint: 0.0.0.0:15268
+`,
+					Ports: []v1.ServicePort{
+						{
+							Name: "port1",
+							Port: 5555,
+						},
+						{
+							Name:     "port2",
+							Port:     5554,
+							Protocol: v1.ProtocolUDP,
+						},
+					},
+					Autoscaler: &AutoscalerSpec{
+						Behavior: &autoscalingv2.HorizontalPodAutoscalerBehavior{
+							ScaleDown: &autoscalingv2.HPAScalingRules{
+								StabilizationWindowSeconds: &three,
+							},
+							ScaleUp: &autoscalingv2.HPAScalingRules{
+								StabilizationWindowSeconds: &five,
+							},
+						},
+						TargetCPUUtilization: &five,
+					},
+				},
+			},
+		},
+		{
+			name: "invalid mode with volume claim templates",
+			otelcol: OpenTelemetryCollector{
+				Spec: OpenTelemetryCollectorSpec{
+					Mode:                 ModeSidecar,
+					VolumeClaimTemplates: []v1.PersistentVolumeClaim{{}, {}},
+				},
+			},
+			expectedErr: "does not support the attribute 'volumeClaimTemplates'",
+		},
+		{
+			name: "invalid mode with tolerations",
+			otelcol: OpenTelemetryCollector{
+				Spec: OpenTelemetryCollectorSpec{
+					Mode:        ModeSidecar,
+					Tolerations: []v1.Toleration{{}, {}},
+				},
+			},
+			expectedErr: "does not support the attribute 'tolerations'",
+		},
+		{
+			name: "invalid mode with target allocator",
+			otelcol: OpenTelemetryCollector{
+				Spec: OpenTelemetryCollectorSpec{
+					Mode: ModeDeployment,
+					TargetAllocator: OpenTelemetryTargetAllocator{
+						Enabled: true,
+					},
+				},
+			},
+			expectedErr: "does not support the target allocation deployment",
+		},
+		{
+			name: "invalid target allocator config",
+			otelcol: OpenTelemetryCollector{
+				Spec: OpenTelemetryCollectorSpec{
+					Mode: ModeStatefulSet,
+					TargetAllocator: OpenTelemetryTargetAllocator{
+						Enabled: true,
+					},
+				},
+			},
+			expectedErr: "the OpenTelemetry Spec Prometheus configuration is incorrect",
+		},
+		{
+			name: "invalid port name",
+			otelcol: OpenTelemetryCollector{
+				Spec: OpenTelemetryCollectorSpec{
+					Ports: []v1.ServicePort{
+						{
+							// this port name contains a non alphanumeric character, which is invalid.
+							Name:     "-test🦄port",
+							Port:     12345,
+							Protocol: v1.ProtocolTCP,
+						},
+					},
+				},
+			},
+			expectedErr: "the OpenTelemetry Spec Ports configuration is incorrect",
+		},
+		{
+			name: "invalid port name, too long",
+			otelcol: OpenTelemetryCollector{
+				Spec: OpenTelemetryCollectorSpec{
+					Ports: []v1.ServicePort{
+						{
+							Name: "aaaabbbbccccdddd", // len: 16, too long
+							Port: 5555,
+						},
+					},
+				},
+			},
+			expectedErr: "the OpenTelemetry Spec Ports configuration is incorrect",
+		},
+		{
+			name: "invalid port num",
+			otelcol: OpenTelemetryCollector{
+				Spec: OpenTelemetryCollectorSpec{
+					Ports: []v1.ServicePort{
+						{
+							Name: "aaaabbbbccccddd", // len: 15
+							// no port set means it's 0, which is invalid
+						},
+					},
+				},
+			},
+			expectedErr: "the OpenTelemetry Spec Ports configuration is incorrect",
+		},
+		{
+			name: "invalid max replicas",
+			otelcol: OpenTelemetryCollector{
+				Spec: OpenTelemetryCollectorSpec{
+					MaxReplicas: &one,
+				},
+			},
+			expectedErr: "maxReplicas should be defined and more than one",
+		},
+		{
+			name: "invalid replicas, greater than max",
+			otelcol: OpenTelemetryCollector{
+				Spec: OpenTelemetryCollectorSpec{
+					MaxReplicas: &three,
+					Replicas:    &five,
+				},
+			},
+			expectedErr: "replicas must not be greater than maxReplicas",
+		},
+		{
+			name: "invalid min replicas, greater than max",
+			otelcol: OpenTelemetryCollector{
+				Spec: OpenTelemetryCollectorSpec{
+					MaxReplicas: &three,
+					MinReplicas: &five,
+				},
+			},
+			expectedErr: "minReplicas must not be greater than maxReplicas",
+		},
+		{
+			name: "invalid min replicas, lesser than 1",
+			otelcol: OpenTelemetryCollector{
+				Spec: OpenTelemetryCollectorSpec{
+					MaxReplicas: &three,
+					MinReplicas: &zero,
+				},
+			},
+			expectedErr: "minReplicas should be one or more",
+		},
+		{
+			name: "invalid autoscaler scale down",
+			otelcol: OpenTelemetryCollector{
+				Spec: OpenTelemetryCollectorSpec{
+					MaxReplicas: &three,
+					Autoscaler: &AutoscalerSpec{
+						Behavior: &autoscalingv2.HorizontalPodAutoscalerBehavior{
+							ScaleDown: &autoscalingv2.HPAScalingRules{
+								StabilizationWindowSeconds: &zero,
+							},
+						},
+					},
+				},
+			},
+			expectedErr: "scaleDown should be one or more",
+		},
+		{
+			name: "invalid autoscaler scale up",
+			otelcol: OpenTelemetryCollector{
+				Spec: OpenTelemetryCollectorSpec{
+					MaxReplicas: &three,
+					Autoscaler: &AutoscalerSpec{
+						Behavior: &autoscalingv2.HorizontalPodAutoscalerBehavior{
+							ScaleUp: &autoscalingv2.HPAScalingRules{
+								StabilizationWindowSeconds: &zero,
+							},
+						},
+					},
+				},
+			},
+			expectedErr: "scaleUp should be one or more",
+		},
+		{
+			name: "invalid autoscaler target cpu utilization",
+			otelcol: OpenTelemetryCollector{
+				Spec: OpenTelemetryCollectorSpec{
+					MaxReplicas: &three,
+					Autoscaler: &AutoscalerSpec{
+						TargetCPUUtilization: &zero,
+					},
+				},
+			},
+			expectedErr: "targetCPUUtilization should be greater than 0 and less than 100",
+		},
+	}
+
+	for _, test := range tests {
+		t.Run(test.name, func(t *testing.T) {
+			err := test.otelcol.validateCRDSpec()
+			if test.expectedErr == "" {
+				assert.NoError(t, err)
+				return
+			}
+			assert.ErrorContains(t, err, test.expectedErr)
+		})
+	}
+}
diff --git a/pkg/collector/container_test.go b/pkg/collector/container_test.go
index 4f95a9012e..a0d7155e59 100644
--- a/pkg/collector/container_test.go
+++ b/pkg/collector/container_test.go
@@ -152,49 +152,6 @@ service:
 				},
 			},
 		},
-		{
-			description: "invalid port name",
-			specConfig:  goodConfig,
-			specPorts: []corev1.ServicePort{
-				{
-					// this port name contains a non alphanumeric character, which is invalid.
-					Name:     "-test🦄port",
-					Port:     12345,
-					Protocol: corev1.ProtocolTCP,
-				},
-			},
-			expectedPorts: []corev1.ContainerPort{
-				{
-					Name:          "examplereceiver",
-					ContainerPort: 12345,
-				},
-				metricContainerPort,
-			},
-		},
-		{
-			description: "long port name",
-			specConfig:  goodConfig,
-			specPorts: []corev1.ServicePort{
-				{
-					// this port name is longer than 15 characters, which is invalid.
-					Name:     "testportaaaabbbb",
-					Port:     5,
-					Protocol: corev1.ProtocolTCP,
-				},
-			},
-			expectedPorts: []corev1.ContainerPort{
-				{
-					Name:          "examplereceiver",
-					ContainerPort: 12345,
-				},
-				metricContainerPort,
-				{
-					Name:          "testportaaaabbb",
-					ContainerPort: 5,
-					Protocol:      corev1.ProtocolTCP,
-				},
-			},
-		},
 		{
 			description: "duplicate port name",
 			specConfig:  goodConfig,