Where to start looking, loss of power on shift

[punkncat]

I have been experiencing a strange loss of power in the shift from first to second, no where else. I am figuring that the fuel pump or system has some issue causing me to run lean, but figured I would post up and see if you think I am on the right track.

Typical high mileage but good running NA. She runs a little wierd while cold with a surge at around 2800RPM, but after it gets warm runs really well. My idle is good and doesn't hunt too much, I do have the fifth gear stall (on clutching). I had noticed a while back that when shifting over 3-4K I would get a hesitation or miss, sort of a brrrppp noise out the tailpipe for a second, but ONLY when shifting from first to second on power. I was horsing around a little on the way home and after taking off from the light got up to about 6K RPM pulling strong. When I shifted into second I reapplied the clutch, foot in gas, and had no power at all until I let out of it and got back in.
I cannot get it to duplicate the problem any other time. I can run 5-6k and just stomp in it with no loss of power, no weird noises, nothing.

My fuel pump does hum, always has. I have a new-ish filter. I was thinking check fuel pressure looking to failing pump or something, but doesn't really explain why I can't duplicate the problem keeping my foot in the gas. Any insight?

[ChadzTurbo]

im not sure of your loss of power but when my 1993 na started making a buzzing sound coming from the fuel pump I changed it. You might be having fuel issues of a failing fuel pump.