4500RPM hesitation

[CC440]

So I've finaly registered and got my new 96 Mark VIII on the road.... just in time to notcie that the car seems to lose a ton of power around 4000-4500 rpm every time I dig into it.

It has all new plugs and wires, new filters, and only 63k miles total. What could be causing this issue? Is it a misfire? The car pulls strong from a stop (will smoke both tires easily) and changing the plugs did help the problem but it's still there.

What could be causing this?

 

[driller]

Sounds like it's loosing fuel pressure.

 

[CC440]

I'm going to have my mechanic check my O2 and MAF sensors also.

Would the pressure drop be caused by a fuel leak or a bad pump?

 

[XLRVIII]

I'm going to have my mechanic check my O2 and MAF sensors also.

Would the pressure drop be caused by a fuel leak or a bad pump?

if the mileage on the car is between 75K and 150K then the fuel pump being weak is a safe bet.

But dont fall prey to the "fuel pump is 300+ dollars" BS that most shops and mechanics give.

There are several options for replacing the fuel pump.
Walboro 255LPH, $100.00 pump.. is what I put on my 95