Engine stalls while driving?

Okay, I will be here.

Roy

That tells me the intake manifold gasket is leaking and drawing from the valley.

That would also explain why it is running rough.

There should be positive pressure from the oil fill cap, not vacuum.

Roy

REMOVAL

NOTE: The intake manifold is a four-piece assembly consisting of the upper intake manifold, the throttle body, the fuel injection supply manifold and the lower intake manifold.

WARNING: Residual pressure remains in fuel system after engine is shut off. This could result in injury or fire when fuel lines are disconnected. Disconnect inertia fuel shutoff switch and crank engine until fuel in lines is used up.

1. Disconnect the battery ground cable at the battery.
2. Remove the air cleaner outlet tube from the throttle body.
3. Remove the accelerator control splash shield and disconnect the throttle cable and bracket assembly.
4. Disconnect all vacuum hoses from the fittings on the upper intake manifold.
5. Disconnect the electrical connections at the throttle body, upper intake manifold, lower intake manifold and fuel injector nozzle tip.
6. Disconnect the fuel supply and return lines at the fuel supply manifold.
7. Remove the bolts securing the ignition coil and bracket assembly to the upper intake manifold.
8. Remove the six nuts securing the upper intake manifold and remove the upper manifold.
9. Remove the valve covers.
10. Remove the intake manifold attaching bolts. Tap the intake manifold lightly with a plastic mallet to break the gasket seal, and lift off the intake manifold assembly.
11. Remove all old gasket material, and sealing compound.

You are welcome.

Roy