I have a 94 civic ex coupe MT. When I run the AC it is very sluggish in low RPMs. In first it almost acts like its going to die out. Once I get into 3rd it seems to run ok. When the AC is off it runs noticeably better. I have had it now for 8 months. I did have the timing and tune up done right when I got it. ANy thoughts. Thanks

 

It's a little engine. When the compressor is engaged, it puts a decent load on the engine, forcing it to work harder to catch up. That's probably one of the reasons people say running the AC makes you use more gas.

 

The compressor has a pulley on it. That pulley has a clutch that is engaged whenever your A/C button is lit up.
When the A/C compressor clutch isn't engaged (A/C button not lit), the pulley spins freely with little to no load, because it is not turning the parts inside of the compressor, only the pulley the belt is on.
When your A/C button is lit (from you having the fan turned on and the A/C button depressed), your compressor clutch engages and the pulley is turning the insides of the compressor along with it, and that puts load on the engine.

 

wow i was gonna tell him smae thing just not nearly as professional you did lol

 

What was replaced for the tune up?

 

you don't need ac crack a window .

 

ah, a helpful post...

 

Our honda motor and small low torque motors and they are slowed by the ac being on. This is normal to loss power when the ac is running. If your car wants to die or stall with the ac on then there is a problem some where. Places to check are ideal and ideal controlling componets (aic valve ect), fuel pump and ignitions components.