Engine problem - loss of power and Pickup

It sounds like a weak fuel pump or the MAF sensor is going bad these guides should help us fix it.

https://www.2carpros.com/articles/engine-has-low-power-output

and

https://www.2carpros.com/articles/how-to-check-fuel-system-pressure-and-regulator

and

https://www.2carpros.com/articles/mass-air-flow-service

Please run down these guides and report back.

I would change the spark plug wires along with the plugs because they had big problems with them at your engine mileage. Please get back to us so it will help others.

Try changing the wires, you should also run the codes even though it might not have a light on.

https://www.2carpros.com/articles/checking-a-service-engine-soon-or-check-engine-light-on-or-flashing

Fuel control comes from the PCM(computer) as it adjusts mixture with input from O2 sensors, MAF and MAP sensors, but I do see a TSB(tech bulliten) for clogged injectors, a good cleaning might be in order. GM states you use Top tier fuels from top tier gas companies with detergent additives to keep injectors clean.

Have the computer scanned for code/s-you have a problem within the engine management system that caused the CEL to turn on-This is your starting point of diagnosis, finding out what's going on.

Callout Component Name
1 Manifold Absolute Pressure (MAP) Sensor
2 EVAP Canister Purge Hose
3 EVAP Service Port
4 Positive Crankcase Ventilation (PCV) Valve
5 Throttle Body
6 EVAP Canister Purge Valve
7 AIR Module,  if equipped

check by bed first, if it is on engine get choke cleaner and spray around hoses, intake etc.

You replaced the sensor, did you also use a scan tool to run the crank variation re-learn process? This is the process but you need a good scan tool to do it.

This video will help

https://youtu.be/sKo7xRWVNqY

Monitor the powertrain control module for DTCs with a scan tool. If other DTCs are set, except DTC P0315, refer to Diagnostic Trouble Code (DTC) List for the applicable DTC that set.

Select the crankshaft position variation learn procedure with a scan tool.
The scan tool instructs you to perform the following:

Accelerate to wide open throttle (WOT).
Release throttle when fuel cut-off occurs.
Engine should not accelerate beyond calibrated RPM value.
Release throttle immediately if value is exceeded.
Block drive wheels.
Set parking brake.
DO NOT apply brake pedal.
Cycle the ignition from OFF to ON.
Apply and hold the brake pedal.
Start and idle engine.
Turn A/C OFF.
Vehicle must remain in Park or Neutral.

The scan tool monitors certain component signals to determine if all the conditions are met to continue with the procedure. The scan tool only displays the condition that inhibits the procedure. The scan tool monitors the following components:
Crankshaft position (CKP) sensors activity-If there is a CKP sensor condition, refer to the applicable DTC that set.
Camshaft position (CMP) sensor activity-If there is a CMP sensor condition, refer to the applicable DTC that set.
Engine coolant temperature (ECT)-If the engine coolant temperature is not warm enough, idle the engine until the engine coolant temperature reaches the correct temperature.

Enable the crankshaft position system variation learn procedure with the scan tool.
Accelerate to WOT.

IMPORTANT: While the learn procedure is in progress, release the throttle immediately when the engine starts to decelerate. The engine control is returned to the operator and the engine responds to throttle position after the learn procedure is complete.

Release when the fuel cut-off occurs.
The scan tool displays Learn Status: Learned this ignition. If the scan tool indicates that DTC P0315 ran and passed, the CKP variation learn procedure is complete. If the scan tool indicates DTC P0315 failed or did not run, refer to DTC P0315. If any other DTCs set, refer to Diagnostic Trouble Code (DTC) List for the applicable DTC that set.
Turn OFF the ignition for 30 seconds after the learn procedure is completed successfully.

Hello, I am Danny.

I am kind of familiar with this problem. It started on my 1997 Silverado as well. You truck might be having a Spider Injection problem. It is located inside the intake manifold. Let me do some research and get back to you. Hope this helps and thanks for using 2CarPros.
Danny-

Hello again.

Have you used a Noid light set to check the number six cylinder fuel Injector pulse/signal in the wiring harness?
Danny-

You are welcome!
Hope to hear from you again sometime if needed. Thanks again for using 2CarPros.
Danny-