FireSquirrel540

I've noticed that my 08 coupe revs up and down when I am stopped at a red light or stop sign with my AC on high. Sometimes it's so bad that the car starts to jump a little forwards like it wants to take off despite me having my foot on the brake. When it starts doing this I turn the AC off and everything goes back to normal, wtf? I sent it to the dealership about a month ago and they found nothing wrong with it at all. My girlfriend drove it the other day and it happened to her and now she refuses to drive the car, lol. has anyone experienced this before? I'm at my wits end and I'm having a friend take a look at it tomorrow. But if he can't find anything and the dealership tells me its fine what am I supposed to do? The last thing I want is for this problem to cause an accident but its been damn near 100 degrees everyday where I live. Any thoughts? I think it may have something to do with the AC compressor?

G37Sam

Well thinking about it, your engine powers your AC. With it on high, the engine will probably rev up to compensate for the added demand. Just move your shifter to N when coming to a complete stop

Dimitry6

this thread is freaky LMAO let me tell you why i wanted to start this thread for some time i have an 08 coupe my self and my car DOES THE SAME exact thing....but the crazy part is i was driving my dads fx for past 2 days so my girlfriend was driving the car because it was reving on her She refuses to drive the car also lol......but yeah i took it to the dealer also they found no problems whats so ever if anyone has an answer please post.....does your car at a red light keep the rpm at like 1 and feels like it just takes off from the dig

G37CPA

I have not experienced that problem here in NC, where it is plenty hot. But then again, I am rarely driving in heavy, slow moving traffic.
Could it be a problem with the thermostat some how? Or a sensor that starts to overheat, shuts off the comperssor briefly, then fires up the a/c again?

cdeez

iTrader: (1)

yeah i get that too..especially when its hot and the ac is blowing on full max.
at first i thought it was because i have a hypertech programmer but there are other posts where this has happened to other members who don't have it.

it is a bit dangerous too and its hard to replicate so when you take it the dealer they have no idea what the heck you are talking about..

hopefully it doesn't take an accident for infiniti to realize there is something wrong...

Fentress24

iTrader: (3)

my 09 manual does this too. not the moving forward thing cause mine is in neutral when at a stop, but the rpms do move up and down sometimes dropping enough where I think its going to stall. thought about mentioning it for a while but never did. Glad to know I am not the only one with this problem.

advan37

iTrader: (3)

I have the same problem since day one i bought this car late 2008, you guys can solve this by reflashing the ECU in any nissan dealer in US. Unfortunately in my case our local dealer refuse to do me ecu reflash coz my car is US specs, so tell today i am searching for someone can do me this.

Dejan

iTrader: (1)

Since I live in Kuwait, I have a lot of experience driving with AC on. I have had this happen with every car I ever owned or drove here, from '76 Mazda 323 through various American, Japanese, German cars right up to my 2010 G37 vert and wife's 2011 Kia Ceratto Coup. AC needs power, and at idle doesnt get enough, so engine revs up a bit. Its not an issue, just press brake firmly while stopped. Dont shift into N, that will reduce life of your AT

maxfinity

Just curious. Why would shifting to neutral reduce the life of the AT?

advan37

iTrader: (3)

Http://www.myg37.com/forums/engine-d...fast-idle.html

FireSquirrel540

Did some research and found this post :

https://www.myg37.com/forums/tsb-tec...g-braking.html

A TSB about intermittent rpm increase when braking for '08 G37's with automatic transmission. Same year and transmission as my car and the same problem I'm experiencing right now. I printed a copy of the TSB and I'm taking it to the dealership with me. Based on what alot of people have posted the problem goes away after a reprograming of the ECM.

advan37

iTrader: (3)

Wish you all the best.

Frankyg37s

iTrader: (3)

weird never happened to me in my 08 coupe

stormgate

iTrader: (2)

reminds me of a civic a buddy of mine built... his MAF was busted (not getting enough juice at idle) so his car would just rev up and down whenever he was under a certain rpm. something like under 1000 rpm, the car would rev to 1200 and down to 500... was pretty crazy sounding

htownboy

Ah the joys of owning a manual transmission! Sorry guys, some of that is just characteristic of an AT car with power.
My cousins CTSv almost launches you into the trunk of any car in front of you when the AC compressor cycles on when stopped in D. Man you gotta' hold the brake hard in that Caddy. I just put the caddy in neutral when stopped if i'm driving. Just remember to shift to D before you hit the gas.
When he tried he kept forgetting and revving the car up while going nowhere. LOL
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