When engine reaches normal operating temperature there is a loss of power

Hi and thanks for using 2CarPros.com. The symptoms you described can be the result of a few things. The first is a partially clogged catalytic converter.

Here are the general symptoms of a converter issue:

https://www.2carpros.com/articles/bad-catalytic-converter-symptoms

Here is how to test one:

https://www.2carpros.com/articles/how-to-test-a-catalytic-converter

If you determine that the converter is bad, here are directions specific to your vehicle for replacement:
Jack up vehicle.
Ensure the catalytic converter is cool.
Remove the four bolts and nuts holding the pipes to the converter.
Remove the converter and two gaskets.
Place new two gaskets on the front and rear pipes.
Install the converter with the bolts and nuts. Torque Value: 32 ft.lb (43 Nm)

I attached three pictures of the converter and its location. Note: The first one is for federal emissions and the second one is for California. I am not sure where you live.

The third picture is that of the converter in your vehicle.

Give this a check and let me know what you find.

Welcome back. The picture you attached is the flex pipe. The vehicle was manufactured with a catalytic converter. If you purchased the vehicle new, I am confused. However, if you purchased it used, it appears someone removed it. Ugh, that leads to new issues. For example, there should be an oxygen sensor which is most likely missing.

Did this problem start all at once? Honestly, without the sensor and converter, the computer most likely does not know what to make the fuel mixture.

Let me know.

Thanks,
Joe

Did you have the distributor out? It may be a tooth off.

No, the shaft is a straight shot. It sounds like to me the engine coolant temperature sensor is not working right when the engine gets hot.

Here is a guide to help you see what you are in for when doing the job:

https://www.2carpros.com/articles/coolant-temperature-sensor-cts-replacement

Here is the location for your car. Check out the diagrams (below). Please let us know what happens.

Cheers, Ken

Please let us know.

The car has full power when cold or is the power just a little better? I am wondering if it is a back pressure issue. Also, I am sure you checked but is the air filter clean?

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

and

https://www.2carpros.com/articles/how-to-test-a-catalytic-converter

Please run down these guides and report back.

Cheers, Ken

It sounds like an ignition issue. Have you tuned up the engine recently with plugs, wires, cap rotor?

https://www.2carpros.com/articles/how-to-tune-up-a-car-engine

Also service the throttle bore.

https://www.2carpros.com/articles/throttle-actuator-service

Please let us know what you find.

Cheers, Ken