Chrysler Repair: Jeep Classic 2000 inline 6 cylinder, coolant temperature sensor, chrysler vehicle

Question
Me jeep started to run verry poorly the only way it would go was to hold it to the floor lack of power also ruff ideling. It was a code 171. I changed the TPS sensor ran great till it warmed up so I then changed the fuel pump and filtere, still a problem then I changed the Map sensor still running poor whats next any ideas? (Runs great till it warms up uses an exsorbent amount of gas and has black soot comming out of the tail pipe.)

Answer
Hi Dan,
The tie to the temperature would suggest taking a look at the coolant temperature sensor. I don't know specifically about your engine but generally it is near the thermostat housing. It has a 2-wire connector and it should exhibit a falling resistance (starts at about 10,000 ohms when cold) as the temperature rises, reaching around 700 to 1000 ohms when fully warmed up. On the Chrysler vehicle you will note that the fans come on when you release the plug with the engine running (lift locking tab gently) which would be an ID verification.
So check that next.
Then if that isn't the answer I would suspect the oxygen sensor as that only come into play when the engine warms up, and if it were off-value or failed then that would be another reason for the symptom you have.
Roland