diff --git a/src/BulletDynamics/ConstraintSolver/btSliderConstraint.cpp b/src/BulletDynamics/ConstraintSolver/btSliderConstraint.cpp
index 2d617217d..1daea39f4 100755
--- a/src/BulletDynamics/ConstraintSolver/btSliderConstraint.cpp
+++ b/src/BulletDynamics/ConstraintSolver/btSliderConstraint.cpp
@@ -344,7 +344,8 @@ void btSliderConstraint::getInfo2(btConstraintInfo2* info)
             info->cfm[nrow] = btScalar(0.0); 
 			btScalar tag_vel = getTargetLinMotorVelocity();
 			btScalar mot_fact = getMotorFactor(m_linPos, m_lowerLinLimit, m_upperLinLimit, tag_vel, info->fps * info->erp);
-			info->m_constraintError[srow] += mot_fact * getTargetLinMotorVelocity();
+//			info->m_constraintError[srow] += mot_fact * getTargetLinMotorVelocity();
+			info->m_constraintError[srow] -= signFact * mot_fact * getTargetLinMotorVelocity();
 			info->m_lowerLimit[srow] += -getMaxLinMotorForce() * info->fps;
 			info->m_upperLimit[srow] += getMaxLinMotorForce() * info->fps;
 		}
diff --git a/src/BulletDynamics/ConstraintSolver/btTypedConstraint.cpp b/src/BulletDynamics/ConstraintSolver/btTypedConstraint.cpp
index b9f6ffc1e..f37110305 100644
--- a/src/BulletDynamics/ConstraintSolver/btTypedConstraint.cpp
+++ b/src/BulletDynamics/ConstraintSolver/btTypedConstraint.cpp
@@ -69,11 +69,11 @@ btScalar btTypedConstraint::getMotorFactor(btScalar pos, btScalar lowLim, btScal
 	}
 	btScalar lim_fact = btScalar(1.0f);
 	btScalar delta_max = vel / timeFact;
-	if(delta_max > btScalar(0.0f))
+	if(delta_max < btScalar(0.0f))
 	{
-		if((pos > lowLim) && (pos < (lowLim + delta_max)))
+		if((pos >= lowLim) && (pos < (lowLim - delta_max)))
 		{
-			lim_fact = (pos  - lowLim) / delta_max;
+			lim_fact = (lowLim - pos) / delta_max;
 		}
 		else if(pos  < lowLim)
 		{
@@ -84,11 +84,11 @@ btScalar btTypedConstraint::getMotorFactor(btScalar pos, btScalar lowLim, btScal
 			lim_fact = btScalar(1.0f);
 		}
 	}
-	else if(delta_max < btScalar(0.0f))
+	else if(delta_max > btScalar(0.0f))
 	{
-		if((pos < uppLim) && (pos > (uppLim + delta_max)))
+		if((pos <= uppLim) && (pos > (uppLim - delta_max)))
 		{
-			lim_fact = (pos - uppLim) / delta_max;
+			lim_fact = (uppLim - pos) / delta_max;
 		}
 		else if(pos  > uppLim)
 		{