I just acquired a 1995 Thunderbird with the 4.6 V8. I got it real cheap because it has serious driveability problems. To make a long story short, I have good compression on all cylinders. I think it is some kind of vaccum leak. I have almost as much vaccum in the crankcase as I do in the intake manifold. As a matter of fact the engine will stall when you remove the oil filler cap. I need some ideas.