Skip the auto shop - Our mechanics make house calls

Q: Idle jumps up and down

asked by on

When I start the truck, the idle jumps up and down and then sounds as if it wants to shut off. Sometimes it will cut off when I'm at a light, and the Check Engine light comes on.

A: Hello. If the Check Engine Light is coming ...

Hello. If the Check Engine Light is coming on, then the first thing that would be helpful would be the computer codes. These can be retrieved with a scan tool. A mechanic would scan the computer first to get these codes to see what the computer is seeing as the problem. It sounds like you may have a faulty air flow sensor or you might need to have the vehicle tuned up. It may also be a faulty vacuum hose on the engine allowing air to enter the engine unmetered. If you do not have a scan tool to check the computer then I would enlist the assistance of a certified mechanic that can diagnose your Check Engine Light and move forward with repairs for your idling issue.

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1000 mechanics are ready to answer your question.
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Ask a Mechanic
(100% Free)

Have a car question? Get free advice from our top-rated mechanics.

Ask A Mechanic
Over 10,000 questions answered!

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

Q: I have a 1991 Legend. Check engine light is on. Tried pulling codes with paper clip in service connector. Light still solid,won't

Hi there, thanks for writing in about your 1991 Acura Legend. I would start by verifying that you are connecting the correct terminals and that you have continuity (i.e., the clip is actually contacting the terminals well). If so, and...

Q: Is your oil change on a 2012 BMW X5 35d Diesel includes tapping off DEF

Hi There, I would recommend checking with our customer service department to confirm this, however it should be included in the oil change service as a precaution in checking all fluids.

Q: My car is making some funny noise from the left side

Does the noise get any worse while steering the vehicle around turns? The squeal tabs on brake pads can make noise when the friction material is almost worn out. A failed wheel bearing will make noise at speed and may...

Related articles

How Do Power Car Windows Increase Passenger Safety?
Power windows are responsible for approximately 2,000 emergency room visits every year. When a power window closes, it exerts enough force to bruise or break bones, crush fingers, or restrict an airway. Though...
What Causes Hoses to Leak?
While the largest part of your engine is mechanical, hydraulics plays a significant role. You’ll find fluids at work in a number of different areas. Your car's fluids include: Engine oil Transmission...
How Much Does a Mechanic Make in Vermont?
Automotive technician jobs in Vermont have an average mechanic salary of $37k, with some mechanics earning a salary of $53k.