Help surging probelm!

[1UZX83]

my uz mx83 has latley been driving a bit off.
just cruzing its fine, but if i put my foot down a bit i get a hesitation and a surge and sometimes a missfire and is not happy free revving like it used to (its alot slower)

to me it feels like the g/box is slipping sopping up some power so thats coming out for rebuild

is there anything else it could be?

 

[spf_lexus]

mine does that too, cant really put my finger on it. I have a centrifugal supercharger and like you said, cruising is great until i try and "feather" some more and its usually going up/down steep hills. City driving is good, tach stays low and revs as needed but 75mph and up doesnt like to free rev. Whats the ssetup on your mx like?

 

[1UZX83]

ive checked all the fluid levels, vac lines, cables etc so only things left to investigate are fuel pump and ignition but really it feels like its the box itself giving up.

setup in my is just 89 crown 1uz auto 3 inch cat back, custom 4-1 extractors, coilovers, 33 gtr brakes,
still sorting wat to do next prob ecu after the box is built, need more power is only 249rwhp at the moment

 

[spf_lexus]

Well since i just blew my head gaskets I wont be able to test drive for a while... anyway I totally agree w/ the box theory, mine feels like the line pressure is out of whack, but adding more "in general" improves the problem. hard to say... ill keep playing around w/ my cables, see if it helps.