☰
GET A QUOTE

Q: I have a question about rough idle

asked by on December 14, 2016

I have been having some starting issues and rough idle for about two months. I've noticed when I start the vehicle I have to crank for at least 2.5 sec. It used to start right up. Now when it's idling in drive at a stop light the truck is vibrating. But the rpms are fine. I've tried replacing the battery with a new one. Same issue. Maybe my fuel injectors need cleaning? I've had a tune up just this year. The vibration isn't big but noticeable. The engine and transmission are still going strong. Maybe the throttle body is dirty?

My car has 264000 miles.
My car has an automatic transmission.

Recommended Services

Car idle is rough Inspection $94.99 - $114.99 Get a Quote
Or For Any Other Auto Repairs Get a Quote

A rough idle may be caused by many different things such as low fuel pressure, low voltage to the fuel injectors, dirty fuel injectors, a vacuum leak, a faulty Oxygen sensor or a dirty or failing idle air control valve. Any of these possibilities relate to fuel delivery issues that will disrupt the normally balanced air/fuel mixture that would otherwise allow the motor to run smoothly. I would recommend having an expert from YourMechanic cometo your location to diagnose your rough idle problem.

Mercury
engine idle
1999
V8-5.0L
Mountaineer
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

What is the correct tire pressure?
The correct tire pressure for your vehicle can be found on the tire and information loading placard. This placard is located on the B-pillar, on the driver’s side, right next to the driver’s side door latch. It contains all the...
Read more
brake lights not working, cant shift out of park
The brake light switch is the most common failure that would make the brake lights inoperative for your car. However, a mere blown fuse can also be the cause. I recommend having a mechanic, such as one from YourMechanic, come...
Read more
Car starting, but not going into gear
The transmission leak would have to be located and fixed then the transmission fluid filled to see if internal damage has been done to the transmission. The leak could be from the transmission or transmission cooler. Once the leak is...
Read more
Cannot get trunk open after using Valet mode
If your vehicle has a valet switch, it should be located on the interior of the vehicle. This switch is often times hidden in the glove compartment somewhere. Whichever button you pressed to activate the valet feature is the same...
Read more
Overheating at the traffic light or while AC is on
You may have a restriction in your radiator or condenser that is preventing the cooling of the respective fluids that go through these parts. Restrictions will cause hot spots and therefore will not allow sufficient cooling of the refrigerant or...
Read more
Dirty throttle body impact on evap purge valve
Hello, the throttle body carbon deposits would not cause the purge valve to fail. The carbon on throttle plate can cause start stall and idle issues that is a service that should be done. The purge valve can fail...
Read more
ABS pump bad soft pedal - 2008 Ford Fusion
Hello - Yes, a replacement ABS pump (https://www.yourmechanic.com/question/abs-pump-is-bad-but-the-part-is-discontinued-by-eric-t) must have the same part number as the pump it is replacing. These units are specific to your vehicle (make/model/production group), and have to match for the software that drives them to...
Read more
My car is misfiring and shaking
The cause of the oil in the spark plug hole is going to be a leaking valve cover gasket and tube seals for the spark plugs are leaking oil into the spark plug holes. You will need to replace valve...
Read more
2008 Crown Victoria police intercepted forward gears slipping but reverse works perfectly?
It is possible that some internal damage may have occurred on your transmission. I would recommend having the major components of your transmission inspected by a qualified transmission specialist to determine the exact cause of this issue.
Read more

Related articles

How Long Can I Leave the AC on While My Engine Is Not Running?
You’ve parked your car, and are sitting inside waiting. Maybe you’re early for work and don’t want to head into...
Read more
Symptoms of a Bad or Failing Idle Control Valve
Common signs include irregular or unusually high idle speed, the Check Engine Light coming on, and stalling while idling.
Read more
How Long Does an Idler Pulley Last?
The The drive belt that is on a car runs nearly all of the major components of the engine. Most of the newer cars on the market have a serpentine belt rather than various V-belts. In order for this belt...
Read more

Browse other content

Services
Cars
Maintenance
Estimates