2001 Dodge Truck Engine appears to misfire when cold

Hi glenn1222, Welcome to 2carpros and TY for the donation

Do you have a check engine light and when was the last tune-up??

Try checking the idle air control motor,intake air temperature and throttle position sensor-also check the fuel pressure

Fuel pressure was at 49psi and constant. After replacing the filter/regulator it is at 53psi and constant.
There is no check engine light now, the code before replacing the filter/regulator was a small fuel leak.

I replaced the cap, rotor, plugs and wires as part of troubleshooting.

How do you test the idle air motor or the air intake temp sensor?

It goes back to normal and stays normal after reving it up on loss of power/misfire. It is only happening about 1 to 2 minutes after starting and lasts 5 to 15 seconds. It would go to normal on its own in about 15 to 20 seconds.

Try cleaning out the idle air control valve and see what happens

I replaced the idle air controller and still have the same problem. Any ideas?

Is the check engine light coming on when problem reappears?

Other causes, that can contribute to the misfiring problem

Defective spark plug.
Inadequate spark/coil,defective spark plug wire.
Lack of compression
False air leakage.
Faulty fuel injectors.
Insufficient fuel pressure.
Contaminated fuel.
EGR valve that is leaking.
Oxygen sensors.
Throttle Position sensor
Idle air control valve

No check engine light, replaced the idle air control valve, replaced the filter/regulator (Solved the hard starting problem), changed the plugs, cap, rotor, plug wires. This only happens for a few seconds and after running for about a minute. If you floor it the problem goes away and doesn't come back.

Test the throttle position sensor's closed idle and wide open throttle voltages-