When fan is on, engine wants to die at idle
 

I'm having an issue with my radiator fan causing a stall. The fan is on a switch and I purchased it this way. I'm not sure why it was put on a switch rather than turning on when the temp increases. Either way, when the fan is on the idle drops so low that it wants to stall out. There are no issues on the highway but in the city it's a p.i.t.a. to deal with because you need the fan on in traffic but you have to keep on the gas to keep it from stalling. Has anyone else dealt with this? I've read that when connected the engine should increase idle when the fan kicks on. Is there anyway to correct this?

Thanks,

Sounds like the fan motor is putting an exceptionally high load on the alternator. I don't think the EEC ups the idle for the fan coming on but rather when the A/C comes on. An A9L EEC for example would not know when the fan comes on or for that matter controls the fan. I could be wrong on that though...