got a 99 maxima and when the ac is on a lot of the times it struggles like helllll to get off the line and under 1800rpms turn ac off and all low end power is back. the only time my car runs strong with A/C on is when i run 93 octane fuel.


does the ac need a oil charge or what could it be? maybe my bad oxygen sensor?

 

"Oil charge"? Im at a loss for words here. First off the ac will always take away low end power, nothing to be done about it except shutting it off. The oil in the ac system never needs to be changed. Furthermore removing all the oil would be one hell of a job, you would need to remove every part and drain it. Simply evacuating and vacuuming it wouldnt get anywhere near all of it out. Deal with it.

 

whats you mean deal with it, I don't have this problem in my 95. feels like a damn Honda civic with AC on its really weak. and by ac charge i mean theirs a pressure can at wall mart called ac oil charge you put on the lines and let the oil in to lubricated the system and allows freon to flow better supposebly.

 

Pag oil won't do u any good for what ur complaining about. The oil will also not make the refrigerant flow any better, its only there to lube the a/c system to avoid component failure.

One time I was curious to see how much power was lost when the A/C was on and when it was off.

So we took 3 different cars which were an Accent, a LeSabre, and an Accord.

Ran 3 base runs, then ran 3 runs with the a/c on.

All 3 cars lost about 30 HP give or take 3-4 HP.

 

Ummm... please tell me you didnt pay to dyno 3 cars 3 different times to find out what power loss, if any, the cars took when the a/c was on...

 

Haha, no it was free

 

ok, but I still dont see a car losing 30hp just by running the A/C

 

Yea kinda hard to believe 'til u see it with ur own eyes.
But those are the results I had.

EDIT: Here's something I found on google relating to A/C power loss http://forums.nasioc.com/forums/show...hreadid=549658

 

I can see that drop. Running the ac definitely makes your car noticeably slower on take off. Hell, why do you think using ac lowers your mileage? Nature of the beast. If you deleted the power steering pump it would also help make the car a little faster. On the mini coopers they use an electric power steering pump, and according to mini it increases HP by I think 4% if I remember right.

 

If your AC currently works, than it obviously has oil and freon. Your system needs to have the proper amount of both, you cant just add an arbitrary amount to it. It would require draining the system, vacuuming it down, and refilling with each according to weight. And anyway, you don't fark with it untill it dies. You run it till it quits, then you have the leak fixed and refill before it goes to shyte. If you really need the extra power turn the AC off, otherwise be happy you have a V6 and only lose the HP you do.

 

If the difference between your 99 and your 95 is that huge, your 99 pump is farked, or your 95 pump isn't pumping very good. Does either car take too long to get cold?

 

if anything the 99 takes a bit longer to cool.

 

Take it to an AC shop for diagnosis, NOT THE DEALERSHIP, see if anything is wrong.