was coming up onto the interstate in 3rd gear stepped into in and it fell flat like it shut off floored it and it came back set cruise at 65 no problem all the way to work coming home it did the same thing i am thinking crank sensor ? any help will help no check engine light Jeep is a 93 4.0 5 speed

 

Check your fuel pressure.

 

picked up a gauge have just over 30 at the rail on idle it you move the throttle it jumps to just under 40 and the flat spot is still there it is acting like an old carb with a bad accelerator pump

 

When was the last time the fuel filter was changed?

 

about a year ago i will change it this week end but i do not think it is a fuel problem could the crank sensor be acting up ?

 

CkPS is a possibility. So is the cam sensor.

Also check your coil. Could be a bad connector to it or it's getting ready to die on you.

All that said, I think you should have 39 psi at idle. Better check that, as I'm going from memory, but if I'm right,, there's your problem.

 

i changed the fuel filter increased the pressure at the rail to about 37 but the flat spot is still there just not as bad if i unhook the vacuum line at the regulator the pressure goes to 40 and no flat spot so regulator ?

 

When was the last time the O2 sensor was changed?