What causes poor fuel usage, loss of power, rough idle, check engine light, and now a weird whistling noise? We have replaced the

Our car all of sudden started having acceleration issues, wouldn't go above 10 miles. The check engine light also came on. It also idles rough , has poor gas mileage, it also has been making a loud revving noise. We replaced the ignition coil pack, spark plugs, boots, crankshaft position sensor. After that the car would at least get up to normal speeds after revving up and shifting hard. We just replaced the ECM, the car went back to no acceleration. We also replaced the fuel filter. I don't know what to do at this point. The car is a 2005 saturn ion level 1.

My car has 189000 mil

Experienced mechanics share their insights in answering this question :
Hi there. It is very possible that the ECU is the source of all of these issues. If you recently replaced the ECU, but it was not reset or programmed by a Saturn dealership, it’s likely the reason for all of these problems. Although ECU’s are sold to consumers, they typically need to be "flashed" or programmed at a dealership to ensure they are properly communicating with all sensors and electrically operated or monitored systems on your vehicle. However, it is also possible that other fuel system components like mass air flow sensor or the fuel injectors themselves are damaged or simply need to be cleaned.

How to Identify and Fix Common car Problems ?

Our sources include academic articles, blog posts, and personal essays from experienced mechanics :

Dirty Fuel Injector

Sometime dirty parts can also be the root cause of a rough idling engine. Fuel injectors disperse fuel into your vehicle`s engine at a precise angle and quantity, to ensure optimal performance. That being said, dirty fuel injectors are also a major contributor to poor gas mileage.

Dirty/Faulty Fuel Injectors – Fuel injection systems play an essential role in starting your vehicle. The system injects fuel and air into the cylinders. If clogged or gummed up, the injectors don`t provide the right mix of fuel and air, resulting in a rough idle or slow acceleration.
The oxygen sensor can affect how much fuel your vehicle`s engine burns. By measuring oxygen levels in the exhaust, the O2 sensor helps to ensure your automobile meters and delivers the correct amount of fuel depending on the demands you place on the engine.
Aside from mechanical issues, other factors can affect gas mileage. Miskelley says bad alignment, improperly inflated tires, poor tread and driving habits can make a difference in how far a gallon of gas goes. “Poorly maintained tires can cause your car to pull harder and do extra work to get going,” says Miskelley.
Oxygen (O2) sensor

An oxygen sensor monitors and analyzes the amount of oxygen in a vehicle`s exhaust system after combustion. A dirty, damaged or malfunctioning O2 sensor (or sensors) affects the air/fuel mixture, causing the engine to idle rough.

Trouble accelerating can come from a few different engine issues. These include, but are not limited to, dirty fuel injectors, low fuel pressure, and restricted airflow. A problem with the mass airflow sensor, throttle position sensor, or engine speed sensor can also cause a car to have difficulty picking up speed.
Common causes of why a car feels sluggish when accelerating include dirty mass air flow sensor (MAF), faulty spark plugs, defective throttle position sensor, clogged catalytic converter, faulty oxygen sensor, clogged air filter, and fuel system malfunctioning.
Most cars have at least two oxygen sensors located throughout the exhaust system; at least one in front of the catalytic converter and one or more downstream from the catalytic converter. The “pre-cat sensor” regulates fuel supply, while the downstream sensor measures the efficiency of the catalytic converter.
The throttle position sensor (TPS) is usually connected to the throttle plate shaft in the throttle body. The TPS reads the angle of the throttle valve and transmits an electrical signal to the PCM. The PCM uses this real-time signal to help calculate or modify fuel injector pulse width, controlling air/fuel mixture.
An idle air control valve, also called an idle air sensor control motor, is an electrically operated valve that controls the amount of air that bypasses the throttle plate in cars with a fuel injection system [source: Autozone]. This causes the idling speed of the engine to change as needed.
Engine Idles Roughly: A rough idling engine could be caused by a failing camshaft position sensor. This issue is more evident when the engine is idling. Hesitation: Hesitation during acceleration is a common issue that you may experience with a bad camshaft sensor.
Causes of a rough idle. Many different problems could result in a rough idle for your car or truck, including: dirty fuel injectors, clogged air filters, bad spark plugs, and a variety of exhaust system issues.
Gas could be leaking from the gas tank, or it could be leaking from somewhere in the engine. If it`s the latter, it could be due to bad engine seals or a leaky fuel injector. This can be particularly dangerous, as gasoline is volatile and prone to combust.

Relevant Questions and Answers :

the most relevant questions and answers related to your specific issue

What causes poor fuel usage, loss of power, rough idle, check engine light, and now a weird whistling noise? We have replaced the
ANSWER : Hi there. It is very possible that the ECU is the source of all of these issues. If you recently replaced the ECU, but it was not reset or programmed by a Saturn dealership, it’s likely the reason for all of these problems. Although ECU’s are sold to consumers, they typically need to be "flashed" or programmed at a dealership to ensure they are properly communicating with all sensors and electrically operated or monitored systems on your vehicle. However, it is also possible that other fuel system components like mass air flow sensor or the fuel injectors themselves are damaged or simply need to be cleaned.

12 so ic 1.8 5 speed motor blow up replaced it idle is rough spits and sputter has no power to go up a hill no check engine light
ANSWER : The issue you are writing in about is common enough that a specific diagnostic, namely a reduced engine power diagnostic is performed by technicians dispatched by YourMechanic. If you request that diagnostic, the responding certified mechanic will get this issue resolved for you. In your circumstance, the vehicle’s powertrain control module (PCM) has undoubtedly stored one or more diagnostic trouble codes that will identify the "general area" in which the fault lies in the engine management controls. Although the throttle control system is a common trouble area with reduced power, there are quite a few other components and systems that could come into play and, of course, there is always the possibility of multiple, or "coincident", faults. Here are some of the possibilities that YourMechanic dispatched technicians would consider:

Defective throttle position (TP) sensor
Defective oxygen sensor
Defective accelerator pedal position (APP) sensor
Loose or damaged wiring
Defective throttle body
Defective powertrain control module (PCM) (not typical; ONLY if a long, long list of other possibilities is ruled out)
Any fault/error that will affect drivability function
Any fault/error that will affect vehicle performance
A fault/error in the emissions system
A fault/error in the throttle control system
A fault/error in the transmission control system

If you request the recommended diagnostic the mechanic will get this resolved for you. If you have further questions or concerns, do not hesitate to re-contact YourMechanic as we are always here to help you.

2012 equinox reduced power light engine light and traction light came on. Lost a lot of power got home and all light except engine
ANSWER : Your car has what is called a "safe mode" that will be engaged by the computer when it detects that something critical has gone wrong related to any of the major components in your engine chassis or power train. This may be related to a number of things, most of which should have been registered in the computer when the check engine light came on. I recommend having an expert from YourMechanic come to your location to inspect your check engine light and diagnose any codes registered by your vehicle’s computer.

Check engine light refuses to go off after engine replaced
ANSWER : Hello there, you have a long series of issues going on with your 2013 Hyundai Sonata. If you keep getting a repeating oil light on than there is likely a fault in that system.

Since this fault has lasted after the engine was replaced it could be a oil pressure sensor, wiring harness fault, ECU fault, oil pump, oil strainer clogged, or low oil pressure.

To diagnose this issue properly you need a complete vehicle inspection to start from square one and identify the root cause of all this.

Reduce engine power / check engine light is on
ANSWER : Hi there. Most of the time, reduced engine power is caused by a restriction of fuel, or the throttle body’s inability to efficiently mix air and fuel. This could be caused by a failing mass air flow sensor, EGR valve or other fuel system components. Since the check engine light is on, you should have a professional mechanic complete an inspection at your location to determine what codes are stored and which components require repair. This should resolve your issue.

Car started to slow down and then the check engine light, battery, and engine oil light came on. What could cause this?
ANSWER : Hi there. It is possible that the battery cable came loose or the wires to the oil pressure sensor has came loose or failed. Check the battery cables and make sure that the terminals are tight and clean. Check the wires to the oil pressure sensor and make sure that they are connected and not broken. If everything looks good, then the oil pressure sensor may have failed. Plus, check the computer for codes and see what is stored. This will lead you to the part that could have failed. I recommend replacing the oil pressure sensor then checking to see if the lights will go out. If you need further assistance troubleshooting your vehicle, then seek out a technician, such as one from Your Mechanic, that can assist you with the warning lights that came on.

Can the power steering return hose problems cause the Check Engine Light to come on?
ANSWER : Hello there, you have several different issues going on with your 2004 Toyota Corolla. Without knowing what the Check Engine Light is, I cannot determine if it has anything to do with the engine shaking or not. The power steering return hose is a commonly replaced hose in the power steering system and is usually replaced due to leaking. A qualified technician, such as one from YourMechanic, will be able to diagnose your Check Engine Light and replace the power steering hose as needed.

Can an open gas cap which causes the Check Engine Light to come on cause the car to not start and the ECM to appear bad?
ANSWER : Yes, there are a lot of things a bad gas cap or open gas cap can affect. If you don’t have a gas cap then you may be experiencing issues with debris getting into your tank or fuel filter and affecting the drive performance. Since the ECM is a costly repair, you may want to have another independent technician diagnose the vehicle’s loss of power. They will be able to confirm the cause of the issue or advise you on another fix.