Anyone ever have this code???

I have had a little trouble with my 02 Trans Am, the lock up converter seems to be acting up. On one question I posted someone let me know that the converter will not lock up until the engine warms up. And lately the converter will lock up when it feels like it. The other day I drove 60 miles and no lock up. One time when the car hit a bump the converter unlocked. The SES light is not on, but the only code I get is

P0118 ... Engine coolant temperature circuit, high input

I have noticed when I start her up and watch the engine warm up the temp gauge will climb slowly then dive down to zero, car will studer and then temp gauge will jump back up to 200 instantly, and away we go.

Now this tells me the lock up converter is not acting up just getting the wrong message from the PCM and doing what it should.

Any Ideas to help me locate my problem will be greatly appreciated.

thanx

Larry Rodriguez
Northern New Mexico

hmm, best guess I could offer never having experianced this is that the coolant temp sensor has died or there is a wiring fault some where.

Agree, check the connection at the ECT or replace it. Mine doesn't lock at part throttle until around 45 MPH and 140* ECT on Predator.

Check the temp. sensor connector, and wires/harness, for broken/open wires. See if you can find any broken, or chafed wires shorting out, by following the harness. Try moving the wires around while it's running to see if they're shorting out. If there's nothing visible, try a new sensor. It's in the Driver's side cyl. head.

thanx, all great advise and I'll do everything I can, or go somewhere for more help, once again thank you all. Greaat Site

I've seen that code with bad ect sensors before. As stated already.
I would get the car up to temp and hook a multimeter up to the sensor and see what it is putting out.... It'll probably be out of the range it uses normally.