Q: Car running really rough

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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.

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