Loss Of Power

My 1993 GMC Sierra four speed with granny gear has no power, it idles fine, but has no power on acceleration and through the gears. I have replaced the TPS sensor hoping that was the problem and it did not work. Also, a tune up has not helped at all. Someone suggested cleaning the TBI, but I can not find anything in the chilton's book on how to take the TBI (Throttle Body Injectors) apart or clean it. If any one has any ideas on how to solve this problem, please let me know. This truck is starting to get on my nerves. :banghead:

Maybe it's the catalytic converter. :22yikes:

Hey,
I posted the following on another thread...

Hey,
I've seen several posts on here related to this situation, and I have an experience which may help.
My 94 Sierra also would run, but would have "nothing" upon accleration. I checked codes and replaced many electrical components in the motor, still the same problem. Then I had a buddy of mine check the fuel pressure inline at the fuel filter, and lo and behold, it was just a trickle.
So, I recommend checking your fuel pressure. If its low, That the good news.
Now, you've got to drop the gas tank to replace the fuel pump. If you cant do it yourself, you might be surprised what this may cost you. Also, in my case, this repair turned out to be a nightmare when the guy who did it for me broke the fuel sending unit when replacing the pump, so now I had no gas gauge ! Rust was a problem with the fuel lines and fittings, so you may look into replacing the whole sending unit and pump together.
Hope this helps, I know it took me 4 ever and a lotta money b4 I even tracked it down to This !! We're Truckin' Now !!
Good Luck.