Q: RPMs fluctuating

asked by on March 19, 2016

I have taken my car to many mechanics but can't seem to find the problem. My car starts fine, but when I start driving it randomly fluctuates between 500 RPMs and 1500 RPMs. I also sometimes get small surges, as if someone was pushing in the gas pedal. I will stall when stopped if I do not push the gas pedal. And the car will also begin jerking when the gas is pushed and released. None of this is consistent; it just happens randomly, daily, or weekly. I replaced the EGR valve and the idle control valve, but that did not solve any of the issues.

Car is stalling Inspection $94.99 - $114.99 Get a Quote

This sounds like there could possibly be a vacuum leak somewhere. My other guess is that the new idle air control valve may also be malfunctioning. If you switched out some parts lately, getting new car parts that are bad right out of the box is starting to become more common, especially with cheaper parts. I would recommend having a mechanic from YourMechanic come to you with their specialized diagnostic equipment to figure out why your car is stalling and acting up the way it has been.

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

Smoke coming from under the hood.
Engine coolant has a very distinct smell when it burns, a sweet candy like smell. If your coolant levels in the radiator aren't dropping, a leak can be ruled out. If the level is low, that means you are either leaking,...
Oil pressure sensor....need changed or just dirty
You may still want to have the system checked in person for a possible bad sensor or connection to the sensor. After washing, you may have washed away some corrosion on the connector to the sensor. If you have a...
Tailights and dash lights stopped working
Hi, check the fuse box and make sure that the fuse hasn't blown. If the fuse is okay, the switch may need to be replaced (https://www.yourmechanic.com/services/headlight-switch-replacement) or there is a connection issue with the circuit. Over time corrosion can build...
Smoke from my exhaust while I am driving down the road
Hey there. Valve stem oil seals (in the cylinder heads) do not last forever and their failure is a possible cause, or contributing cause, to oil getting into the combustion chambers and then burning. Of course, it is also possible...
Service ESC
The Electronic Stability Control (ESC) system is your car's traction control system. The traction control system monitors the steering stability of the vehicle and engages when loss of traction has been detected. This is done by the use of electronic...
I went to AAmco because my engine light was on! They did a diagnostic and came up with 2 codes. intake runner position sensor cir
Diagnostic Trouble Codes, such as the two codes that were retrieved at the first shop, cannot be used to "directly" condemn parts. Rather, these Codes are merely clues that are used to inform an actual diagnostic. But, short of an...
Electrical issues with Chevy Cobalt SS 07
Hi there. It appears you have a serious electrical mess on your hands. In most cases, instead of trying to trace an issue where there are "customized alterations", it may be a better idea to completely rewire the vehicle's ignition...
Pre collision system
Hi there. In the owner manual inside your glove box there should be a section on adjusting the PCS settings and restoring to factory settings. If you're not able to find these instructions, since your car is new, it would...
Car died while exiting the free way. Went to restart and couldn't even get it to rev. What could it be?
This may be related to many different possibilities, some of which may be related to a lack of spark or possibly timing issues and some of which may be related to a fuel delivery problem or a combination of both....

Related articles

A Buyer’s Guide to the 2012 Lincoln Navigator
The The Lincoln Navigator was the flagship luxury SUV which laid the roadmap for its followers such as the Cadillac Escalade and the Lexus LX. Lincoln truly adhered to a philosophy of “go big or go home” on this 8-passenger...
A Buyer’s Guide to the 2012 Lincoln MKS
The The 2012 Lincoln MKS offers a roomy interior with high-end features that deliver a luxury driving experience. Available with two different V6 engines, both of which offer power, and a cabin that deadens outside sound, you’ll be able to...
How Long Does a Throttle Controller Last?
In In order for your accelerator pedal to actually work as you push down on it, it needs to be connected to the throttle. In older model vehicles there was a mechanical link that connected the throttle body and the...