Q: Car has rough idling, occasionally seems it would stall

asked by on June 23, 2016

My car has around 170,000 miles on it. After I had some bigger repairs done on the car at the dealership, some issues started happening. The car started running differently. For instance, it would occasionally idle as it would stall, especially when stopped at the traffic light. I went to the dealer again for this issue, but they couldn't solve it. There were no error codes. They had the fuel injectors checked. They are in good condition according to them. I tried putting fuel injector and fuel line cleaner and when the latter is in the gas tank, there are no issues. I was suggested to have all the fuel injcetors replaced. Could you give me some advice as I am not sure I want to spend that kind of money if it's not neccesary?

Hello. Replacing the fuel injectors will not cause this. If it only stalls at idle, I would clean the throttle body first. If it is dirty, then this will occur. If it is fine, then it may be an air flow sensor or possibly a crank sensor. Both are common failures on this vehicle. I usually use a scan tool to monitor these sensors when the engine stalls to see what changes. If you need to have this done, consider YourMechanic, as a certified mechanic can come to your home or office to diagnose your rough idling problem and determine what actions should be taken.

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


Experienced Mechanic?

Earn up to $70/hr

What others are asking

Bouncy suspension, bottoms out, is it broken?
A certified mechanic, such as one from YourMechanic, needs to examine your suspension system (https://www.yourmechanic.com/book/?mktg_jid=358) to identify any shocks that are leaking. It sounds like your shocks are losing hydraulic pressure which accounts for the excessive bounce over hard bumps....
How do I display the trip A/B feature?
Your truck has a Base Message Center that keeps track of your vehicle's system functions. You can use this message center to display your vehicle's information and features. The Trip A/B feature logs the distance traveled for different trips. To...
Rattling sound coming from car while idling
Hi, many others have reported similar issues. There is a metal heat shield on the exhaust manifold that can get bent or loose over time. I would recommend getting a certified technician to inspect the exhaust system (https://www.yourmechanic.com/services/noise-from-engine-or-exhaust-inspection) to see...
Charging 14 volts and drops to 11 volts then back and forth
This is most likely caused by a poor connection to the voltage regulator or the alternator. Try to lightly wiggle the alternator wires all the way from the battery to the alternator and regulator connections to see if you can...
Tension strut replacement
Hello there, one of the commonly replaced parts on the 2009 BMW 535i is the hydraulic fluid filled bushings. These suspension components wear over time from absorbing the road shock. When the fluid filled bushings leak, it is important to...
My car's gas pedal goes out and the car won't drive anymore if my RPM reaches the number 3 on the gauge.
Hello, I would start by extracting the problem codes from engine management and the transmission as well. You don't mention it, but surely the Check Engine light is on at this point. These codes will help determine a strategy for...
Hard shifting from 1st to 2nd
Hi there. The problem with your transmission is the 1 to 2 shift accumulator has either a broken spring or a split o-ring on the piston. You can replace this very easily. Drop the pan and gasket. If you just...
My Lexus RX300 cannot start. i Noticed the fuel pump is not working. However it works when i connect a different power cable. is i
If the fuel pump powers on with a separate power source, you issue lies in signaling the fuel pump. The fuel pump relay can be at fault. Also other sensors like the crankshaft position sensor. On most vehicles, the engine...
Oil and battery light keeps coming on
It sounds like you may have a weak battery, a failing voltage regulator or failing alternator. As you may know, the alternator charges the battery while the engine runs by generating amperage and recharging the battery while the engine turns...

Related articles

How to Clean Plastic Car Parts
Your Your car is made of several types of materials, though most of the parts that are for aesthetics are plastic. Plastic is used because it is easily molded to a desired shape and can be tinted to match the...
How to Clean Brake Dust
Brake Brake dust (https://www.yourmechanic.com/article/what-is-brake-dust) is residue that accumulates on a car’s wheels over time. The dust comes from the brake pads (https://www.yourmechanic.com/article/what-are-brake-pads-made-of), which wear down over time from the friction of braking. The pads slowly wear down (https://www.yourmechanic.com/article/how-long-do-brake-pads-last_2), and the...
How to Keep Your Car’s Acrylic Paint Looking Brand New
Acrylic Acrylic paint was extremely popular in older cars, and can still be found on many cars today. While there are many different reasons for manufacturers, auto body specialists, and car owners alike to use acrylic paint, there is one...