diff --git a/compiler/fir/modularized-tests/tests/org/jetbrains/kotlin/fir/FE1FullPipelineModularizedTest.kt b/compiler/fir/modularized-tests/tests/org/jetbrains/kotlin/fir/FE1FullPipelineModularizedTest.kt
index dec5bf3436d..dd29a517a3d 100644
--- a/compiler/fir/modularized-tests/tests/org/jetbrains/kotlin/fir/FE1FullPipelineModularizedTest.kt
+++ b/compiler/fir/modularized-tests/tests/org/jetbrains/kotlin/fir/FE1FullPipelineModularizedTest.kt
@@ -28,6 +28,7 @@ class FE1FullPipelineModularizedTest : AbstractFullPipelineModularizedTest() {
     }
 
     fun testTotalKotlin() {
+        isolate()
         for (i in 0 until PASSES) {
             println("Pass $i")
             runTestOnce(i)
diff --git a/compiler/fir/modularized-tests/tests/org/jetbrains/kotlin/fir/FullPipelineModularizedTest.kt b/compiler/fir/modularized-tests/tests/org/jetbrains/kotlin/fir/FullPipelineModularizedTest.kt
index eecdebc12c6..d3a7e625efd 100644
--- a/compiler/fir/modularized-tests/tests/org/jetbrains/kotlin/fir/FullPipelineModularizedTest.kt
+++ b/compiler/fir/modularized-tests/tests/org/jetbrains/kotlin/fir/FullPipelineModularizedTest.kt
@@ -26,6 +26,7 @@ class FullPipelineModularizedTest : AbstractFullPipelineModularizedTest() {
     }
 
     fun testTotalKotlin() {
+        isolate()
         for (i in 0 until PASSES) {
             println("Pass $i")
             runTestOnce(i)