Q: Car idle sputters and engine dies when AC clutch engages

asked by on June 25, 2017

When a/c is turned on, and car is at idle or in motion, the engine sputters and dies when the a/c clutch engages and rpms are increased. The a/c compressor clutch intermittently engages and disengages, I don't know if this is normal for make and model for my vehicle. Also, the clutch makes a loud "clunk" noise when it disengages and when it re-engages. I don't know if the clutch should spin continuously with the belt or not.

My car has 113000 miles.
My car has an automatic transmission.

Hi there. In most cases, when the AC compressor and clutch engage, it will draw extra ’power’ from the engine and cause the idle to slightly drop. However, this can cause existing issues to be amplified. For example, if you have dirty fuel injectors, mass air flow sensor or EGR valve on the vehicle, the activation of the compressor clutch will make the symptoms worse and more noticeable. However, if the compressor bearings or clutch is dragging, it can "bog" down the motor even more. It’s a good idea to have a professional mechanic come to your location to complete a car idle is rough inspection to determine if it’s a normal fuel system issue or if the AC system is the source of this problem.

Was this answer helpful?
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

Get a quote

What others are asking

After oil change - no oil registers on dip stick 2015 ford edge

Hi there. When oil is changed, the filter is removed and less than 2 oz. of residual oil will remain in oil lines and throughout the motor. When it's added and the new filter is not primed (meaning not filled...

My car won't catch in gear. It is slipping right pass the gears.

Hi there. Your shift cable may have come loose on the transmission shift linkage connection either at the transmission or at the steering column linkage under the dash on steering column. Have the cable ends inspected to see if the...

my car jerks and seems like it wants to shut down when im at a red light and i roll the windows up lights seem to dim out

This sounds like it could be two separate problems. You may have been on the right track with the battery, but if the voltage drops while the engine is running, that sounds more like a charging system problem. It might...

Related articles

The Top 5 Selling Cars in Delaware in 2012
Delaware Delaware offers a variety of weather, which means drivers have to be prepared for both the mild and the treacherous. In previous years, the best-selling vehicles have included the Honda Civic, Accord and CR-V, along with the Toyota Camry....
2012 Ford F-150 vs. 2012 Chevrolet Silverado: Which One Should I Buy?
When you’re ready to really get some work done, there’s nothing like a full size pickup truck. These trucks are ready to haul a big load and really get in there and get busy. SUVs are great for moving people,...
The Top 10 Most Problematic Cars
All cars have issues, from grinding brakes to gasket leaks. The Ford Explorer's and Honda Civic's bad transmissions rank them as the most problematic.