As you said when you tramp brake engine idles ruf and then cuts out 2 things
1 return valve in brake vacuem pipe from intake to booster
2 Brake booster sucking air
ts Elliot died because of emphysema
The idle speed on modern computer controlled vehicles is not adjustable. If you are having idle problems you will need to take the car to a mechanic.
Yes, it can cause low/unstable idle or die off at idle.
Firstly check the level of the fluid. If low this can cause a clicking and a humming when wheels are held on full lock at engine idle. If not think about replacing the pump.
a vacuum leak can cause high idle
vacuum leak. check the hoses for cracks in vacuum hoses or intake.
Opel has this common fault, usually around 100 000 kms, the idle sensor gives in and needs to be changed. At first it will be off and on, then is gets worst, my advice is get it sorted before it gets worse.
I blown head gasket can cause an engine miss which one cause a rough idle.
A lack of fuel. Can cause your vehicle not to idle. A dirty fuel filter can cause the same problem. The fuel injection pump can also cause your vehicle to not idle properly.
What can cause a 1195 Oldsmobile to idle rough?
No, that has nothing to do with idle speed.
You can adjust the idle.