PO171 & PO420

I have the PO420 & PO171 codes in my 2005 Toyota Tacoma 2.7L. I have replaced the Intake manifold gasket, the Mass Airflow Sensor and both the cats. When I start it up my truck lopes high to low RPM's until it warms up then has a good idle. I have sprayed carb cleaner all over the intake, PVC and all over the engine with no change in rpm. Would the O2 sensor cause the car to lope? Would the Fuel pump cause that, the filter is built in to the pump on that model. I just put in some injector cleaner and I am totally willing to change the injectors if I was sure that was the problem, but I was hopping someone could give me some insight. It seems to me like an intake leak would cause this problem, but I am not detecting one anywhere. Any advice would be greatly appreciated.

 

171 is a lean code. What do your fuel trims look like?

 

I don't have a computer so I haven't looked. I'm guessing I should buy a computer and check out what the trims look like. Is there a guide for what they should look like?

 

There is a basic rule of thumb for fuel trims but some manufacture tolerances are different. A fuel pressure reading wouldn't be a bad idea to get either. Also check your o2 voltages.