I've a 2003 Durango with the 4.7 litre engine and 205k miles.

Description of the problem:
If the engine is cold, it start perfect and has no problems. It runs great.
But if the engine is warm or maybe at 90 degress and I start the car after a break and stop after a few foots it begins to stumble.
The speed is around 500 rpm. The light at the speedometer flares slight. Sometimes it dies.
Sometimes, not always, the check engine light goes on. The OBD diagnostic says TPS Sensor High input P0123 and P0121.
The last time, the cooler runs at high speed while driving.
I replaced the TPS Sensor and the fuel pump and deleted the codes. But the problem is still there and the check engine light goes sometimes on after the problem
emerges the next time.
It doesn't matter if it's cold or warm outside.
To remove the problem while standing is only to push the throttle control to the bottom. Then it runs perfect.
I disconnected the TPS Sensor to check if the problem is still there. It's still the same.
Then I measured the voltage at the TPS and everything was fine.

That was only one time: After the car stood a few days, I started it and after a few meters at a stop sign the problem came on.
The coolerfan runs at high speed.

I don't know what else could be the problem. There are no more codes or anything.

I only drive the car for the next 4 month but in this time more than 10k miles.
Normally I would not spend any more money but it's annoying and I don't want to have a breakdown.

Any tips or solutions?
Thanks

 

Did you disconnect the battery before the TPS replacement?

 

Yes and I checked the wires to the TPS.

 

Nobody any idea?

I read a bit and found some capabilities:
- bad coolant temperature sensor
- problem with the suction pressure or O2 Sensor

Could it useful to check it?