Showing check engine,and loosing power. 2005 Toyota Isis

It is a Toyota Isis 2000cc,d4dengine,it has started showing check engine sometimes,but lately it is showing throughout,I went to a mechanic today and we put new transmission oil,but still I can see its behaving the same,please advice.thanks.
My car has an automatic transmission.
Experienced mechanics share their insights in answering this question :
Hello – loss of power can be caused by many failures. The first task is to determine the problem codes being set with the Check Engine light. This will guide diagnosis, and avoid unnecessary replacement of parts. I would recommend a thorough inspection of engine electrical and fuel systems by a mobile, professional mechanic, such as one from YourMechanic, who will come to your location, diagnose this problem, give you an accurate assessment of damage and cost estimate for repairs.

How to Identify and Fix Common car Problems ?

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The most likely issue is that a component is clogged. A clogged fuel filter is the most common reason, although a loss of power in your car could also indicate problems with the fuel pump or fuel line. Impurities or debris may be blocking the system, which causes the loss of power in a car.
The check engine light can either come on and stay lit or blink, depending on the type of problem. Typically, when a check engine light flashes rapidly, it indicates a power loss in the vehicle or something even more urgent.
The reasons for a check engine light turning on can range from something minor like a loose gas cap to something more serious like a faulty catalytic converter. It could even be a sign of internal engine failure. Ignoring the problem can turn a potentially quick fix into a costly and time-consuming repair.
Your check engine light, or Malfunction Indicator Lamp, could mean a number of things. It could be a misfiring engine, a broken oxygen sensor, or simply a loose gas cap.
The Mass Airflow Sensor (MAF) measures the amount of air the car needs to accelerate. Once it gets that measurement it sends this information to the ECU which notifies the throttle to open accordingly. If the MAF is faulty and not measuring the airflow properly then you could experience a serious loss in power.
Culprits include a dirty fuel filter, clogged fuel tank strainer, clogged or failing fuel injectors, or a defective fuel pump. On most vehicles replacing the fuel filter is a DIY operation.
A misfiring engine means the spark plug wires are not firing properly. This causes many problems, like increased exhaust emissions, reduced fuel economy, and reduced engine power.
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.
If the check engine light illuminates, it will either blink or remain constantly illuminated, depending on the problem. A blinking light, or in some cars a red light instead of a yellow or orange light, indicates a problem that needs immediate attention. Either way, you should have the vehicle checked by a mechanic.
Your car should not jerk around, surge forward, or stall when you apply the gas, and if it does, chances are that your engine is well on the way to failure. Performance issues always signal a deeper problem, and in this case, that problem can be worn out spark plugs, clogged fuel lines, or even failing pistons.
Can you drive a car with the engine light on? It`s okay to drive for a few miles, but be sure to schedule an inspection of the engine as soon as possible. If the check engine light comes on while you`re driving, don`t panic! Pay attention and see if the car is driving any differently than normal.
Oxygen sensors are a common cause of “check engine” lights. This sensor is located in the emission control system of your car, and is standard on all vehicles manufactured after 1980. The oxygen sensors are used to ensure that your engine is burning the correct amount of fuel, and running at peak performance.
Low engine oil, loose cables, and a clogged catalytic converter commonly cause reduced engine power. Tighten loose cables or clean your oxygen and mass air flow sensors to bypass reduced engine power. Replace your battery or catalytic converter if they are damaged to override reduced engine power.
The reduced engine power warning light shows that something has reduced the flow of fuel and/or air to the engine. It often turns on when a car needs maintenance or repair and doesn`t mean your vehicle is about to break down, but it could be a good time for an oil change.
Low engine oil, loose cables, and a clogged catalytic converter commonly cause reduced engine power. Tighten loose cables or clean your oxygen and mass air flow sensors to bypass reduced engine power. Replace your battery or catalytic converter if they are damaged to override reduced engine power.
The check engine light disappears when the issue that caused it to come on no longer exists. This usually happens when the problem resolves itself even without visiting your mechanic. Remember that your car computer keeps on performing tests on the engine while you`re driving.

Relevant Questions and Answers :

the most relevant questions and answers related to your specific issue

Showing check engine,and loosing power. 2005 Toyota Isis
ANSWER : Hello – loss of power can be caused by many failures. The first task is to determine the problem codes being set with the Check Engine light. This will guide diagnosis, and avoid unnecessary replacement of parts. I would recommend a thorough inspection of engine electrical and fuel systems by a mobile, professional mechanic, such as one from YourMechanic, who will come to your location, diagnose this problem, give you an accurate assessment of damage and cost estimate for repairs.

2010 Toyota Prius. When I made a sharp turn, all check engine and warning lights to check ‘Hybrid System’ came on.
ANSWER : In order to reset the Maintenance Schedule light:

1) Without touching Brake pedal, press "Start" button twice,

2) Press and hold the "STRIP" button until you see "TRIP A" on display,

3) Turn Ignition to "OFF",

4) Press and hold "ODO Reset" button, AND,

5) Continue to hold ODO Reset Press "START" button twice (w/o touching the Brake pedal),

6) Continue to hold ODO Reset until "000000 Miles" appears on display, and Maintenance Light turns off.

A certified YourMechanic technician can also come to your location to help perform an inspection of your vehicle to diagnose your issues with uphill acceleration and recommend any necessary repairs.

My car shows the Check Engine Light and DPF lights and coil light on the dashboard. What action should I take?
ANSWER : Hi. The EGR valve needs to be replaced and the passages to the EGR need to be cleaned. The EGR location is very tricky to get to so you may need a professional technician (such as one from YourMechanic) who can complete this repair. The diesel particulate filter (DPF) filter should also be replaced and the housing for the filter should be inspected for damage due to the people stealing your filter.

My check power steering symbol is showing up on my Lexus 2012 RX 350 and the car wont move an inch.
ANSWER : Hello. It sounds like you either have a broken belt or a voltage loss in the vehicle. If the battery is failing or if the alternator is failing then this will occur. I would check these first by having them load tested and make sure that the engine drive belt did not break. If you are going to have this repaired, consider YourMechanic, as a certified mechanic can come to you to [diagnose why the steering will not work] https://www.yourmechanic.com/services/brakes-steering-and-suspension-inspection

Loosing power while driving
ANSWER : If you were getting O2 sensor codes, and you are losing power, then you may need to check to see if the fuel pressure is low or the fuel filter is getting clogged. These both can cause the engine to loose power and can cause the O2 codes. Check to see if the pressure is low, and if so, replace the fuel filter. If you need help with doing this, reach out to a certified mechanic who can help you diagnose the lose of power you’re experiencing.

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.

I have a 2002 toyota camry LE engine wich i want to use on a 2004 toyota camry XLE .is my 02 toyota camry engine compatible ?
ANSWER : Hi there. Assuming that both engines are the same size, the compatibility of "fitting" should be OK. However, since this is a service we don’t offer, we’re not best suited to provide the best advice on this. I can tell you that a common problem have with replacing motors is communication with the ECU. In most cases, it will require reprogramming by a specialist in order for all the systems to work correctly.

Truck cranks but won’t start.
ANSWER : Hi and thanks for contacting YourMechanic. The EFI supplies power to the C/OPN relay. Check the wiring from the EFI and the C/OPN relay for any breaks. Use a digital ohm meter and check for a complete circuit in the wiring from the EFI and the C/OPN relay. If the meter reads high resistance or OL, then the wiring is burned and needs repaired. If the meter reads good with .05 ohms or resistance, then check the pin connectors and make sure that they are touching the relay. If you need further assistance troubleshooting your no start situation, then seek out a technician, such as one from YourMechanic, that can assist you.