look for vaccum leak(vaccum control switch, diaphragm valves or vaccum lines).
A vaccum leak simply means vaccum is leaking.And as far as fixing it you have to find it first it could be a hose with a hole in it. or a loose hose. theres many ways to find the vaccum leak. To put it easier think of a vaccum cleaner being hooked to a bunch of hoses anywhere theres suction besides the open ends would be a vaccum leak.
What does it cost to repair a vaccum leak on a 2001 deville
Replace the seal.
A vaccum Leak
Most likely cause is a vaccum leak. The controls move components via vaccum. When there is a slow leak, the vaccum decreases while sitting idle and increases as the rpm of the engine increase. Diagnosong where leak is can be difficult and recommed seeking proffessional assistance from reputable mechanic.
vaccum leak somewhere. or a boost leak Spyda
vaccum leak
Vaccum leak?
You have a vaccum leak. When you step on the brake, vaccum is being used to help the power assist, thus lessening the amount in the engine available to leak. The reason it goes away when you accelerate is that vaccum drops low on acceleration too.
usually a vaccum leak will not allow the cruise to "set" When you break, the vaccum from the brake cylinder lets the cruise go.
You have a vaccum leak. You need to fix this now or your fiero will become junk. Most likely vaccum hoses are melted.