Originally Posted by Supersnake04
To use or not to use
DONT use it
The 'intake manifold wash' style is HORRIBLE for your engine.
Let me set the scene for you....
Years and years of driving your engine with a working PCV system. The PCV system is throwing oily vapor down your intake manifold, which it clings to the sides. Your air filter does not catch all debris, thus letting said debris cling to your intake manifold runners. Over time and heat, these particles build up and harden to carbon-like deposits. Left there, they pose no hazards to your engine except for the performance loss of reduced air flow.
Now take all those deposits, and wash them into your engine's combustion chamber.
Your rings and pistons take a nice dosage of sediment.
You have just taken life off of your engine. For what? A 'cleaning'? A cleaning that should've involved taking off the upper intake manifold?
I have no idea why people use the intake foam. Its awful.