Hesitation...power loss

Synned said:

Well today I check the ACT sensor. It was about 90* out and the voltage was a little low.
1.72 volts across both wires, which according to jrichter means it should be around 120* outside.
I'm not sure if its really that hot in the intake tubing or if the sensor is just off.
My ECT was also very very low, but I guess the coolant is around 200* anyway

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You may already know this and have these figures but if you don't here they are:

Engine Coolant Temperature Sensor (ECT)

First check for any codes (I think Hissin mentioned this earlier). A bad ECT will set Code 116, 117, or 118

The resistance (ohm) values increases as the sensor temperature (ECT)decreases and decreases when the sensor temperature increases.

You should check the resistance value of the ECT when it is completely cold (50 to 65*F = 58,750 to 40,500 ohms) and then check at normal operating temperatures (180-220 = 3,600-1,840 ohms). You can also perform the test by placing the sensor in a pan of hot water (similar to testing a thermostat).

If those tests are negative check the reference voltage with the key on and engine not running and it should read approx. 5 volts.


Intake Air Temperature Sensor (IAT)

First check for any codes. A bad IAT will set codes 112, 113, or 114.

Low temperatures produces a high resistance value (ohm) and vice versa. Check the resistance of the IAT both cold and warm. The values are 68*F= 27.3 K-ohms and 212*F=2.0 K-ohms. Simply put the resistance when testing both cold and hot should exhibit a change, if no change then the IAT should be replaced. Also, check the reference voltage of the IAT and it should also be approx. 5 volts.