Top 7 Toyota 1AZ-FE 2.0L Engine Problems & Reliability!

Top 7 Toyota 1AZ-FE 2.0L Engine Problems & Reliability!

August 17, 2023 0 By CarGuy

Are you interested in purchasing a Toyota with the 1AZ-FE engine and you want to learn more about the 1AZ-FE 2.0L engine problems? If that’s the case, you are at the right place because in this article there will be a lot to cover on this engine.

Doing good research before you purchase a used vehicle is always a good idea. You just don’t want to end up with a problematic vehicle that will be a headache. And not only that, but a couple of repairs can also quickly drain your wallet. And this is why we are here to help you out with this problem and see how you can avoid some of these issues.

So, what will we cover today? First, we are going to learn some of the specs of this engine. Then, we are going to learn more about the applications of this engine. Once we clear that out of our way, we are going to learn more about the common Toyota 1AZ-FE 2.0L engine problems and the reliability of this engine. So, without further ado, let’s dive into the article.

Toyota 1AZ-FE 2.0L Engine Specifications

Back in 2000, Toyota decided to introduce the AZ family of engines and replace the old S-series of engines that were produced since the 80s.

This new AZ engine design has brought a lot of new upgrades compared to the older engine design. The new engine got an all-aluminum block with cast iron cylinder liners. Which made the AZ engine a lot lightweight compared to its competition.

The cylinder head is also aluminum on the AZ engine and implements a DOHC layout with 4 valves per cylinder. The engine also uses variable valve timing (VVT-i).

The important thing to note is that in this family, there were a few different engines. But for this article, we are primarily interested in the 1AZ-FE engine and the Toyota 1AZ-FE 2.0L engine problems.

This is the 2.0L engine that was used in Toyota models. Not to confuse it with the 2.4L Toyota Engine. Although many of the problems these engines have are interchangeable. Meaning that both engines have the same issues.

Nevertheless here are the full specs of the 1AZ-FE 2.0L engine.

  • Configuration: Inline-4
  • Displacement: 2.0L
  • Cylinder Bore: 86 mm
  • Piston Stroke: 86 mm
  • Block & Head Material: Aluminum
  • Head Design: DOHC, 4 valves per cylinder
  • Variable Valve Timing: Yes, VVT-i
  • Compression Ratio: 9.6:1
  • Fuel Injection: MPI
  • Horsepower: 148 – 150 hp
  • Torque: 142 lb-ft (193 N-m)

Toyota 1AZ-FE 2.0L Engine Applications

Now before we dive into the Toyota 1AZ-FE 2.0L engine problems, let’s learn in which applications you can find this engine.

  • 2002 – 2009 Toyota Camry/Aurion
  • 2000 – 2003 Toyota RAV4
  • 2003 – 2006 Toyota RAV4 Europe
  • 2001 – 2009 Toyota Ipsum
  • 2004 – 2008 Toyota Wish

Common Toyota 1AZ-FE 2.0L Engine Problems

Now let’s list the common problems with the 1AZ-FE engine.

  • Spark Plug & Coil Failure
  • Dirty Throttle Body
  • Vibrations At Idle
  • Oil Consumption
  • Cylinder Head Bolt Failure
  • Water Pump Failure
  • You Need To Adjust Valves

Now that we covered the common Toyota 1AZ-FE 2.0L engine problems, we can move on and further elaborate on these issues.

We need to make sure to learn when and how these problems appear, the symptoms they make, and how difficult they are to fix. So, without further ado, let’s dive into the problems.

1. Spark Plug & Coil Failure

The first problem on our list is the spark plug and ignition coil failure. And honestly, these are common problems on these older engines.

Whenever the engine gets at a certain mileage, these ignition components take the toll. These problems are exacerbated when you have a situation like oil consumption that is normal for these engines.

The electrodes get covered in soot and they tend to fail. So, as the miles climb on these engines, the likelihood to change these components will be higher and higher.

Luckily, they are not that expensive to fix. You can also do this DIY if you want to wrench on your car.

Common symptoms associated with this problem are the check engine light, engine misfires, rough engine idle, and poor fuel economy.

Now let’s move on to the next  Toyota 1AZ-FE 2.0L engine problems.

2. Dirty Throttle Body

A problem with the throttle body was also noted. So, what is a throttle body, and why is this a problem?

The throttle body is the component that opens and closes to allow air to go into the intake. Sometimes this throttle body becomes dirty.

A dirty throttle body can malfunction and cause problems. This is because of carbon deposits that stick to the throttle body and ruin its performance.

Sometimes these deposits are so excessive that the only way around the problem is to replace the throttle body.

This is why we recommend cleaning the throttle body every once in a while in order to avoid some symptoms like check engine light, high idle, low idle, engine stall, poor fuel economy, and poor engine performance.

3. Vibrations At Idle

A lot of owners reported that this engine tends to create more vibrations at idle compared to other engines.

So, the engine is not one of the quietest around, that’s sure. Even though this is not really a problem because the engine works well, only the operation is a bit on the louder side.

Now let’s move on to the next Toyota 1AZ-FE 2.0L engine problems.

4. Oil Consumption

Oil consumption is a fairly common problem with the AZ engine. This issue is common in the 2.4L engine and the 2.0L is no exception.

This oil consumption often happens by design, the oil scraper rings are not doing their job and they allow oil to pass through. This problem occurs at 150,000 miles. Sometimes even sooner.

This oil that ends up in the combustion chamber will start to burn and whenever you have a problem like this, you will have high oil consumption.

Unfortunately, this problem is not solvable. The block has to be replaced along with the pistons and crankshaft.

Symptoms that indicate oil consumption are low oil levels and blue smoke from the exhaust.

5. Cylinder Head Bolt Failure

Another common problem with the AZ family of engines is the cylinder head bolt failure. This problem troubles the 2.4L and the 2.0L is no exception.

There are a few bolts on the black side of the engine that can crack and allow coolant leaks to develop.

These engines when they start to develop these issues, there will be leaks from the back side of the engine block.

The way to solve the problem is to replace the head gasket and the head bolts. If the engine is overheated, you will also need to refinish the cylinder head as well.

Now let’s move on to the next Toyota 1AZ-FE 2.0L engine problems.

6. Water Pump Failure

The water pump is prone to failure on these engines. This component has a recommended lifespan and if you go over it, the pump will fail.

Sometimes these pumps even fail prematurely. Common symptoms of a failing water pump are coolant leaks and noises coming from the water pump.

This is why we recommend that you track these symptoms in order to avoid your engine overheating in the process.

7. You Need To Adjust Valves

This engine does not use hydraulic lifters, this means that the valves will have to be manually adjusted every 100,000 miles or so.

Sometimes even sooner. Whenever they start to fail, you will notice that there will be some ticking noises coming from the top of the valvetrain.

An experienced mechanic can easily adjust these valves in a few minutes. A con in this situation is that you will also have to replace the valve cover gasket since the valve cover has to be removed in the process.

Toyota 1AZ-FE 2.0L Engine Reliability

The reliability of this engine is decent, it has some issues but overall, will last for about 200,000 miles with no major issues.

Eventually, when the miles creep up, the engine will start to burn a lot of oil and there will be blue smoke from the exhaust.

This means that you need a new short block or a rebuild kit to rebuild the engine.


In this article, we have covered quite a bit when it comes to the 1AZ-FE engine by Toyota.

First, we learned more about the specs, as well as the applications of this 2.0L engine. Then, we covered all the Toyota 1AZ-FE 2.0L engine problems that we could find and learned whether it is reliable or not.


How Much Horsepower Does The 1AZ-FE Have?

This engine produces anywhere between 148 and 150 horsepower. The power numbers are pretty modest because it is mainly intended for economy vehicles.

Is The 1AZ-FE Engine Reliable?

Yes, the engine is fairly reliable if it has low miles. If the miles are high, the engine will start to drink engine oil excessively. This is a clear situation that you need to perform an engine rebuild on your 1AZ-FE engine.

What Are The Common Toyota 1AZ-FE 2.0L Engine Problems?

Common problems with this engine are issues associated with the throttle body, high oil consumption, and head bolt failures. These are the most common ones.