93 suburban no power

my 93 sub. has a 454 and seems to have no power when pulling my 25' camper when on cruise going up hills in drops 15-20 mph. I pull in overdrive bucause it seems to pull better than in just drive, Ihave replaced the cap rotor plugs wires and it still seems to have no power. Also when it sits for a week or two the battery goes dead I had it checked at a shop and they tested for a draw and said it tested good but 2 weeks later tried to start it and the battery was very low and it would not start it drained the battery the battery is brand new when it was tested at the shop they said iut was the battery. thanks Rick

my 93 sub. has a 454 and seems to have no power when pulling my 25' camper when on cruise going up hills in drops 15-20 mph. I pull in overdrive bucause it seems to pull better than in just drive, Ihave replaced the cap rotor plugs wires and it still seems to have no power. Also when it sits for a week or two the battery goes dead I had it checked at a shop and they tested for a draw and said it tested good but 2 weeks later tried to start it and the battery was very low and it would not start it drained the battery the battery is brand new when it was tested at the shop they said iut was the battery. thanks Rick

For the power issues, it could be lots of different things. When is the last time a tuneup was done? Fuel filter replaced?

Things this could be:
Timing chain worn out
Plugged Cat or Exhaust
Too low fuel pressure or clogged injectors
Ignition (wires and/or coil)
MAP Sensor
Knock Sensor and/or EST

//2000CAYukon

For the power issues, it could be lots of different things. When is the last time a tuneup was done? Fuel filter replaced?

Things this could be:
Timing chain worn out
Plugged Cat or Exhaust
Too low fuel pressure or clogged injectors
Ignition (wires and/or coil)
MAP Sensor
Knock Sensor and/or EST

//2000CAYukonreplaced fuel filter 2 months ago also replaced plugs wires dist rotor and ran some injector cleaner in it.