1992 K1500 misfires under load

[JerryWonder]

Truck idles fine but runs like garbage on the road. I have replaced the fuel pump, fuel filter, injectors, rebuilt the TBI, replaced the coil, and map sensor. Please help. No check engine light

 

[HotWheelsBurban]

Have you replaced the distributor cap, rotor, spark plugs, plug wires or module?

 

[JerryWonder]

No, I pulled the cap and looked at the rotor and cap and it looked good.

 

[Schurkey]

Truck idles fine but runs like garbage on the road. I have replaced the fuel pump, fuel filter,

What is the fuel pressure under load?

injectors, rebuilt the TBI, replaced the coil, and map sensor. Please help. No check engine light

Have you replaced the distributor cap, rotor, spark plugs, plug wires or module?

No, I pulled the cap and looked at the rotor and cap and it looked good.

So you haven't verified the spark plugs and plug wires, or the O2 sensor, and fuel pressure?

Worth testing the cranking compression.

Connect a scan tool, look at the data stream. Verify every sensor when the truck is running good, and when it's running bad. Also look at the computer outputs--IAC, EGR, spark advance, etc. Worthwhile looking for "codes", too.

How old is the O2 sensor?

How old is the catalyst(s)?