I have been having some trouble with my 1996, 4 cylinder, 2.7 liter tacoma. When I shift gears, the engine lags, and sometimes cuts out. It feels much the same as if I were to try shifting into 2nd gear from a stand-still, but it happens while I’m driving, shifting into any new gear. I rapidly lose speed; I don’t just coast. When the engine cuts out, I still have electrical power (radio still plays, lights work, etc.). I tested the clutch (w/ handbrake on, shift into 4th, give gas, let up on clutch, see what happens), and it stalls as I release the clutch (I think this is appropriate). I have done this several times with the same result. The engine does not seem to idle roughly, although the check engine light has recently flashed on (as of 5 minutes ago). I don’t know where the transmission fluid stands, as I don’t know how to check it. All other fluids are good. This problem has been going on for 2 days. Thanks.
Fuel pump, or something else like a fuel filter? I had similar symptoms in my 2000 Tacoma and the fuel pump was to blame. I think this would be pretty easy for a shop to diagnose.
If it is a bad fuel pump I recommend you replace it with the Toyota replacement (ie not something from an auto parts store).