vacuum leaks seem to do alot of bad, i dont think i have a leak but would like to check just so i no 4 sure. whats the best way to make sure?? also how do u check to see if your intake manifold is leaking??

 

take a can of starting fluid and go under the hood while the motor is running. Start spraying around the runners, plenum, intake, TB, wherever there COULD be a leak. If you hear the engine revs increase when you spray in a certain spot, there's a leak. If the rev's don't ever increase no matter where you spray, no leaky leaky. You can use anything flammable. Propane works well and leaves no moisture, brake clean works too b/c it's real flammable and dries quickly.

 

Could any of this damage un-clearcoated polished alum. mainly my plenum and runners?

 

Starting fluid isn't going to hurt aluminum.