Nissan Repair: delayed shift when A/C is on., power steering fluid, 67 camaro

Question
My daughter's 1991 Maxima has 199,000 but still runs good. I change the fliuds regularly and maintain all systems since she and my grandaughter ride everyday. She complained of a transmission problem( not going into gear) but I can't find any problem. Anyhow, I changed the engine oil, trans fluid and power steering fluid as a matter of course. I used the "high milage" type trans fluid. The only thing I can se out of the ordinary is that when the A/C is on the shifting is delayed and shifts @ a higer rpm. Being an OLD Chevy guy ( 454 man ) I try but don't know much about computer control cars. Since the transmission shifts fine without the A/C on, I don't think it's in the tranny but in control of the engine. Just a guess.LOL Any help surely will be much appreciated. Thank you Ed

Answer
Hi Ed -

Well, I am like you - the muscle car days, were the best! I had a '67 camaro 350 which I souped up, you know, racing cam, headers, and 8 miles a gallon!! LOL

Anyway, The A/C puts load on the engine, thus may change the shifting pattern, because it changes the RPM. Why it was not doing that before is beyond me. Fiorst of all, I would like you to put an additive that has really helped past clients of mine. It is called AT205. In my past experiences, it has helped many with shifting problems, even cars that do not go into gear (park to drive). Here in Hawaii, Carquest carries it. I assume you can Google it if you cannot find it, but you can also let me kow, and I will send it to you. It is not that expensive.

Let me know how it goes -
aloha
calvin