Q: Rough idle when A/C on

asked by on August 08, 2016

Lately I've noticed my 2004 infiniti fx45 idles rough when the a/c is running and I'm idling at a light; to the point where it feels it may shut off. When a/c is off car runs strong or when I'm driving with a/c on it runs great. It only has issues when I'm in idle. Any idea of what the issue could be?

My car has 214000 miles.
My car has an automatic transmission.

Clean Throttle Body $94.17 - $328.59 Get a Quote
Car idle is rough Inspection $79.99 - $99.99 Get a Quote

Your engine throttle body and idle air control may be clogged with carbon and engine is idling too low with A/C on causing the rough idle. Have the idle control valve and throttle cleaned out. You may also have the injection system cleaned and the combustion system cleaned to reduce carbon buildup on the back of the valves. If you want to have this looked at, a certified professional from YourMechanic can come to your car’s location to diagnose your rough idling issue and let you know what needs repair.

The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

What others are asking

Advice on changing automatic transmission fluid on an Infinity G35

If it has a dipstick on it, then yes, you can just drop the pan, do all that stuff and fill it up and put the dipstick. A lot of them don't have dipsticks so make sure it has a...

Runs rough and misfires

Hello. The trigger system that your codes may be referring to could be the crankshaft or camshaft position sensors. Many engine management systems use these signals as a trigger point for their ignition systems. It could be possible that there...

Faulty O2 sensor

Hi, it is possible for the O2 sensor to not turn on the Check Engine Light if it is failing slowly. It's also possible for leaks to occur, which can throw off the sensors readings. I would recommend having a...

My car won't start even with a new battery

It is possible that maybe the connections on the battery terminal ends are not tight enough or secured properly. I would recommend getting a wrench or socket to try and tighten up the battery terminal ends to ensure a good...

Best motor oil for a 04 bmw 325ci ow40w or 5w40w full synthetic

The difference between these two oils is primarily the viscosity or thickness of the oil. Depending on the brand, there may be a number of other additives in play as well, however the most important component of the oil is...

Not sure what part my car needs. It it shakes when I'm getting off the high way. And it feels like it's dancing in the front.

Hello, thank you for writing in. When dealing with a shake or wobble, its always best to start with the simplest options and work your way up in complexity. Make sure your tires are properly inflated, and have the tires...

What else can it be besides the fuel pump, relay, and fuel filter if my tahoe putts

The check engine light means the ECM has stored a code in memory. The code may be indicating the problem causing the problem you are having. The problem sounds like you are having an issue with the fuel control, such...

Where is the oxygen sensor location for Bank 2, Sensor 1?

The passenger side of the engine is bank one sensor one and bank one sensor two. The driver's side of the engine is bank two sensor one and bank two sensor two. This is the standard for all vehicles with...

P0016 and P0018 keep popping up.

Hi, thanks for writing in. These codes are both camshaft and crankshaft correlation codes. While these codes can be caused by a faulty sensor, more often they indicate a problem with the engine timing components. This could be anything from...

Related articles

What Typically Causes the Heating or AC to Stop Working?
While both the heating and AC are connected - to an extent - within your car, they’re actually...
How Often Does an AC System Need to Get Recharged?
Your car’s air conditioning system is a lot like your home’s central heating and air, and even more closely resembles the system that keeps...
How Long Does an AC Condenser Last?
Your Your car’s air conditioner system has a lot of different components, including the compressor, the receiver dryer, the hoses, the evaporator, and the condenser. The condenser is the component that converts gas into cooled liquid. Most people do not...