Q: Car running really rough

asked by on

I own a Mazda Tribute. And it's been running on like 4 cylinders we've tested the coil packs and changed them and the same with spark plugs. We cannot seem to find the problem. It is automatic and it sounds like it wants to stall. Just won't idle. It stalled me the other day we've also checked the cat converter and that's fine.
My car has an automatic transmission.

Hi There, If you have tested and checked all coil packs and spark plugs with everything checking out properly, it may be likely that your issue is related to fuel delivery such as low fuel pressure or potentially a dirty or faulty idle control valve. The idle air control valve monitors the air intake as it is mixed with fuel prior to being injected into the engine at low speeds and at idle. This valve is controlled by the vehicle’s computer and will adjust idle speed based upon other measurements such as engine temperature, intake air temperature and electrical system load or voltage. This is also an important function when starting the motor as it allows the motor to run and idle on it’s own once the motor fires. When you accelerate, the engine RPM increases, and as you let off the gas, the RPM slowly returns to the normal idling speed with the help of the idle air control valve making the transition from a higher RPM back down to idle speed while adjusting the air/fuel ratio constantly to allow this to happen smoothly. When the engine RPM drops below the normal range of about ~800 RPM, this often times will cause the engine to stall indicating a dirty or faulty idle air control valve. I would recommend having an expert from YourMechanic come to your location to diagnose and inspect your vehicle.

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
  1. Home
  2. Questions
  3. Car running really rough

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: has a very bad misfire.specified ignition coil has been changed

A single cylinder misfire won't keep a motor from running, so whatever the issue is, the #2 cylinder misfire is likely a symptom of the problem. With 180,000 miles on the vehicle I would wonder if there is a problem...

Q: I think I got ripped off by my auto mechanic

From what you've described you may have blown the head gasket when you overheated the engine. The shop pressure tested and repaired the leaking hose but the engine may have already gotten damaged when it initially overheated. If you want...

Q: Speedometer not working in a 2004 Chrysler PT Cruiser

There may be a wiring issue in the speedometer circuit, or the gauge in the instrument cluster may be bad. I would ask for help from one of the mechanics at YourMechanic to help diagnose and repair your speedometer concern....

Related articles

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...
P0240 OBD-II Trouble Code: Turbocharger Boost Sensor B Circuit Range/Performance
P0240 code definition Turbocharger Boost Sensor B Circuit Range/Performance What the P0240 code means P0240 is an OBD-II generic code triggered when the Engine Control Module (ECM) detects the intake boost...
What are the Car Pool Rules in Hawaii?
Hawaii is widely regarded as a land of vacation and relaxation, and as such, its scenic roads and routes are far better known than the state’s freeways. But, as with all...