engine missfiring

[fulltrottlels7]

that temp. sensor is place under the intake manifold? i have 3 scanner NGS,genesis 3.0 and IDS.... i already check the data of that sensor but its read normal... thats why im just relay on intake system,coils, injectors,spark plug and PCM....... what is the best thing to do to check that sensor.....

[rhandwor]

First make sure your scanner is reading the correct temperature. Is it degrees C or F I'm retired but the thermostat was either 192 or 195 degrees F . What you need to determine is what the temperature is in the morning on start up and what the sensor says it is reading. If its zero F outside and the computer thinks its 40 degrees F the mixture will be set wrong. From what you say it runs fine when the thermostat opens. I think it is changing from closed to open loop at the wrong temperature.
If you have a thermometer you can check at 160 degrees and verify what the sensor says.

[dashmore]

If you haven't figured this out, There is a component bolted on the intake tube / throttle body area (I will have to look at it to give you a precise location). In that component there is an orifice that reads the vacuum being created in the intake and works with a spring reaction, If that orifices collects dirt on gets smaller due to dirt, it will create the Low Idle issue (not sure if that is what your getting). Its about 600 RPM and tough to get it to come up till the engine warms up. Remove the component and clean the orifice (you can buy a spray cleaner at the parts store / ask for the right stuff). This was passed on to me by a knowledgable tech and resolved the IDLE issue on my car. I had to do it 3 times over a 6-9 month period but have not had to do it again for 3 yrs. (I say that and now i'm sure it will be back soon)