Decrease power at 40 mPH to 50 Mph

Hello, I just bought a 1993 Crown Vic with a few issues. It is losing power at about 40 MPH. As I press the gas pedal I feel a hesitation followed by vibration. If i keep depressing the pedal this will continue until about 52 Mph and then it will become unnoticeable. When I'm in the 40 - 50 MPH range and I start to get the vibration, I let go of the pedal and then re-apply and this seems to help. I keep repeating the process until I'm passed 50.

Any idea what's goin on??

I have cleaned the throttle body, and am now going to replace the mass airflow sensor with a used part. After that, will probably move on to TPS.

It was the spark plugs!!!

Nice. I hope you didn't have to go through too much to get that handled. Thank you for coming back and posting the fix. It could help someone with similar problems find it using the search function.