diff --git a/src/oneD/StFlow.cpp b/src/oneD/StFlow.cpp
index 02fb636ca..ee7130a41 100644
--- a/src/oneD/StFlow.cpp
+++ b/src/oneD/StFlow.cpp
@@ -1027,12 +1027,11 @@ void StFlow::evalRightBoundary(double* x, double* rsd, int* diag, double rdt)
     diag[index(c_offset_Y + rightExcessSpecies(), j)] = 0;
     if (m_usesLambda) {
         rsd[index(c_offset_U, j)] = rho_u(x, j);
-        rsd[index(c_offset_L, j)] = lambda(x, j);
     } else {
         rsd[index(c_offset_U, j)] = rho_u(x, j) - rho_u(x, j-1);
-        rsd[index(c_offset_L, j)] = lambda(x, j) - lambda(x, j-1);
     }
 
+    rsd[index(c_offset_L, j)] = lambda(x, j) - lambda(x, j-1);
     diag[index(c_offset_L, j)] = 0;
     rsd[index(c_offset_T, j)] = T(x, j);
 }