95 3.8 surge with a/c

[uzzo2]

i'm getting an engine surge when turning the a/c on was wondering if anyone knew what it might be, took the iac valve off the other day and cleaned it, that seemed to help but was not paying any attention as to whether it ws happening with or without the a/c on thanks for any help. also should mention that it is only surging when in gear not when in neutral or park.

[wiswind]

I have noticed on my '96 3.8L that you can "feel" the load as the A/C compressor engages.
Also.....when cruising down the highway.....the RPM's will often spike up some, very briefly, when the A/C compressor kicks in.
I am guessing that what is happening......the PCM senses the additional load and bumps the RPMs up.....and unlocks the torque converter temporarily.
When this spike up happens.....I do not feel much difference in speed....no loading down.....or boost in speed....so the overall effect is a smoother ride when the A/C engages......

The thing to note is that there is a big increase in load on the engine when the A/C compressor is engaged....
IF this is the only time that you notice an issue.....it may be normal.....or if it is severe.....you might have the A/C system checked to make sure that the pressures / charge are correct.