Not so fast. The IAC motor will constantly adjust it's position even under driving conditions to accommodate loading such as when the AC kicks in. It also is adjusted to compensate for power steering load control as well as off-idle dashpot.

So, always check it. It also may have an issue with the stepper motor moving in and out or, locking the pintle in place.

If it's old and, it's in bad shape, it is quite possibly affecting the A/F ratio. However, it would be quite noticeable under no load conditions if the pintle valve were open too far thus allowing too much air to enter the TB. The idle speed would increase and, if and when you gave it gas, the RPM speed would ramp up and then remain up for a brief moment with a long ramp down to where it was. Again, this is the pintle valve is sticking in idle position. Sometimes they are fine at idle but, during running condition, they fail to operate properly thus allowing air to pass by thus leaning out the A/F ratio which, at that time, the fuel trims would compensate for it to a certain degree along with the amount of voltage at the PCM input coming from the O2 sensor.

NOTE: I don't recommend Bosch O2 sensors. I recommend to use only NTK OEM sensors that work much better and are designed as well as manufactured to a higher degree.

CM

 

Update..... Replaceing the front o2 sensor seems to have fixed the lean problem. I ran her pretty good and is still idleing like it should. If i can just figure out why the ac seems to kick out on acceleration then kicks back on after i ease to cruising speed i will be in great shape!! Thanks for the helpfull suggestions on my lean problem guys.

 

The AC issue is mostly due to low-vac condition thus, when the engine idle returns to within normal cruising speeds, it kicks back in again. The vacuum controls the vents and, there was a TSB about that as seen here: http://dodgeram.info/tsb/1996/24-01-96a.htm

That along with installing a vacuum reservoir (secondary actually) was mentioned. But, you may also have a vacuum leak as well.

CM