Top 5 Problems Toyota Corolla Sedan 9th Generation 2002-08

Summary

In this informative video, Len from 1A Auto discusses the top five problems commonly found in 9th Gen Toyota Corollas. He covers issues with the master cylinder and pushrod, timing chain tensioner, oil pressure problems related to the VVT solenoid, starter malfunctions, and EVAP system leaks. He also touches on common headlamp assembly issues and emphasizes the importance of regular maintenance to ensure the longevity of the vehicle.

Takeaways

• 🚗 The 9th Gen Toyota Corolla has common issues with the master cylinder, which can cause brake pressure problems.
• 🔧 A clogged master cylinder port or a faulty pushrod can lead to inadequate brake function, requiring adjustment or replacement.
• 🔑 The pushrod between the brake pedal and master cylinder must be properly adjusted when replacing the master cylinder to avoid brake pedal feel issues.
• 🔄 The timing chain tensioner, located on the passenger side rear of the engine, can leak oil and fail, causing a rattle noise and potential engine damage.
• 🛠️ An oil change and replacement of the timing chain tensioner kit are recommended to address related issues.
• 📉 Oil pressure problems can be indicated by an erratic engine idle and may involve the VVT solenoid, requiring inspection and possible replacement.
• 🛢️ Checking the oil level and condition, along with cleaning the oil screen behind the drain plug, can help diagnose oil pressure issues.
• 🔧 The starter may fail after 100,000 miles, causing a 'clunk' sound or a failure to start the vehicle, and may require replacement.
• 🔌 Starter problems can also be due to poor electrical connections, indicated by corrosion or buildup on the wiring.
• 💨 An EVAP system leak is typically signaled by a check engine light and can involve the gas cap, hoses, or the charcoal canister.
• 🌫️ The charcoal canister and its associated hoses and air filter should be inspected for damage or blockage in the event of an EVAP leak.
• 💡 Headlamp assemblies on older models like the 9th Gen Corolla are prone to degradation and may require replacement for optimal performance.

Q & A

What is the main safety issue discussed in the video for the 9th Gen Toyota Corolla?

The main safety issue discussed is the problem with the master cylinder, which can either be clogged ports inside the cylinder or issues with the pushrod between the master cylinder and the brake booster.

Where is the master cylinder located in a 9th Gen Toyota Corolla?

The master cylinder is located under the hood on the driver's side, up against the firewall.

What is the purpose of the pushrod in the braking system of the 9th Gen Toyota Corolla?

The pushrod connects the brake pedal to the master cylinder and needs to be adjusted to ensure proper brake pressure and pedal feel.

What symptom might indicate a problem with the master cylinder or its pushrod?

Symptoms include a low brake pedal that requires excessive stepping before engaging or brakes that feel like they are hanging up due to over-adjustment.

What is the second problem discussed in the video related to the engine of the 9th Gen Toyota Corolla?

The second problem is related to the timing chain tensioner, which can cause a rattle noise if it fails due to insufficient oil pressure.

Where is the timing chain tensioner located in the engine of the 9th Gen Toyota Corolla?

The timing chain tensioner is located on the passenger side rear of the engine.

What is the recommended action if the timing chain tensioner is found to be leaking oil?

The recommended action is to replace the timing chain tensioner with a kit that includes a new seal, and to perform an oil change.

What oil pressure issue is discussed in the video related to the VVT solenoid of the 9th Gen Toyota Corolla?

The VVT solenoid can cause an unstable idle with the engine RPM fluctuating if there is an issue with oil pressure or if the solenoid itself is faulty.

How can one check for potential issues with the oil system of the 9th Gen Toyota Corolla?

One can check the oil level and condition, inspect the oil drain plug and screen for blockages, and clean the screen if necessary.

What is the common issue with the starter in the 9th Gen Toyota Corolla after reaching 100,000 miles?

A common issue is the starter failing to engage properly, which can be heard as a 'clunk, clunk, clunk' sound when attempting to start the vehicle.

What is the recommended approach to diagnosing an EVAP system leak in the 9th Gen Toyota Corolla?

The recommended approach is to start with checking the gas cap seal, then inspect the charcoal canister and its hoses for damage or blockages, and use a scanner to pull any diagnostic codes.

What is a common issue with the headlamp assemblies in older Corollas and how can it be addressed?

A common issue is the degradation of plastic lamp assemblies, which can be temporarily fixed or permanently resolved by replacing both headlamp assemblies.

Outlines

00:00

🚗 Master Cylinder and Brake Issues in 9th Gen Toyota Corollas

This paragraph discusses common safety issues related to the master cylinder in 9th Generation Toyota Corollas. The master cylinder, located under the hood on the driver's side, can develop problems with internal ports clogging or the pushrod between the master cylinder and brake booster malfunctioning. Symptoms include a soft brake pedal or brakes that feel over-adjusted. The solution involves replacing the master cylinder and adjusting the pushrod. Additionally, the importance of checking and adjusting the brake system after any replacement is highlighted.

05:01

🔧 Engine Problems: Timing Chain Tensioner and Oil Pressure Issues

The second paragraph addresses engine problems, starting with the timing chain tensioner, which is prone to oil leaks and can cause a rattling noise from the timing chain if it fails. The paragraph suggests using a mirror to inspect the tensioner and replacing it with a kit that includes a new seal. It also covers oil pressure issues, including the importance of regular oil changes and checking the oil level and condition. The VVT solenoid is identified as another potential source of oil pressure problems, manifesting as an unstable engine idle. The solution may involve cleaning the oil screen and possibly replacing the VVT solenoid or inspecting the camshaft if issues persist.

Keywords

💡Master Cylinder

The master cylinder is a key component in a vehicle's braking system. It converts the mechanical force applied to the brake pedal into hydraulic pressure, which then activates the brakes. In the video, the master cylinder is identified as a common issue in 9th Gen Toyota Corollas, where it can become clogged or its pushrod may need adjustment, affecting the brake's performance.

💡Brake Booster

The brake booster is a device that assists the driver in applying greater braking force by using intake manifold vacuum to reduce the amount of pedal effort required. In the script, it is mentioned in relation to the master cylinder, where a faulty pushrod connection can lead to improper brake adjustment.

💡Pushrod

A pushrod is a mechanical linkage that transmits force from the brake pedal to the master cylinder. In the video, it is highlighted that if the master cylinder is replaced without adjusting the pushrod, it can result in a low brake pedal feel or over-adjustment, affecting the braking system's efficiency.

💡Timing Chain Tensioner

The timing chain tensioner is a part of the engine that maintains the correct tension on the timing chain, which synchronizes the rotation of the crankshaft and camshaft. In the script, it is noted that oil leaks can cause low pressure, leading to a rattle noise from the timing chain, indicating a potential tensioner issue.

💡Oil Pressure

Oil pressure is the force exerted by the engine oil within the engine's lubrication system. The script mentions that insufficient oil pressure can lead to problems with the timing chain tensioner and other components, potentially causing engine damage.

💡VVT Solenoid

The VVT, or Variable Valve Timing, solenoid is an electrical component that controls the timing of the engine valves for optimal performance. In the video, it is discussed as a potential cause for unstable engine idle, where the RPM fluctuates erratically.

💡EVAP System

EVAP, or Evaporative Emission Control System, is designed to prevent fuel vapors from escaping into the atmosphere. The script describes diagnosing an EVAP system leak, which can trigger the check engine light and is often fixed by checking the gas cap seal or the charcoal canister.

💡Check Engine Light

The check engine light is a dashboard indicator that signals potential issues detected by the vehicle's onboard diagnostics system. In the context of the video, it is associated with an EVAP system leak and requires a diagnostic scan to identify the specific problem.

💡Starter

The starter is the device that initiates the engine's operation by turning the engine over. The video script discusses common starter issues in high-mileage vehicles, such as a noisy Bendix gear or a failure to turn the engine over, requiring replacement.

💡Bendix Gear

The Bendix gear is a part of the starter that engages with the engine's flywheel to start the engine. In the script, a noisy Bendix gear is mentioned as an early sign of a failing starter, which may eventually lead to a complete starter replacement.

💡Headlamp Assemblies

Headlamp assemblies are the components that house the headlights and ensure they function correctly. The video script mentions that older Corollas commonly have issues with plastic headlamp assemblies, which may require replacement for a permanent fix.

Highlights

The 9th Gen Toyota Corolla's master cylinder issue and its location under the hood on the driver's side.

Two common problems with the master cylinder: clogged ports and pushrod adjustment issues.

The importance of adjusting the pushrod when replacing the master cylinder to avoid brake issues.

The second problem discussed is the timing chain tensioner issue, located on the passenger side rear of the engine.

The timing chain tensioner's reliance on oil pressure and the common occurrence of oil leaks.

Symptoms of a faulty timing chain tensioner, such as a rattle noise from the timing chain.

1A Auto's kit for replacing the timing chain tensioner, including a seal.

The third problem of oil pressure issues, particularly with the VVT solenoid.

Diagnosing oil pressure issues by checking the oil level and condition.

The role of the drain plug and the importance of cleaning the screen behind it for oil flow.

Checking for deposits or metal debris as indicators of engine issues.

The fourth problem of starter issues after 100,000 miles and the symptoms of a failing starter.

The process of diagnosing a starter problem, including checking the wiring for corrosion.

EVAP system leak as the fifth problem, indicated by a check engine light.

Common places to check for an EVAP system leak, starting with the gas cap seal.

Inspecting the charcoal canister and hoses for damage or blockage related to EVAP system issues.

The importance of regular maintenance to prevent engine problems and extend its life.

Additional common issue with headlamp assemblies on older Corollas and the suggestion to replace them.

Transcripts

Hey, friends.

It's Len here from one 1A Auto.

Today, we have a 9th Gen Toyota Corolla in the studio, and I wanna go over some of the

top problems, so let's get started.

Now, for our first problem, of course, we're gonna talk about a safety issue because that's

just how I roll.

For these particular vehicles, what we've come to find is that there's an issue with

the master cylinder.

The master cylinder is located right underneath your hood on the driver's side, up against

the firewall.

It's this right here, has your brake fluid in it.

What tends to happen with the master cylinder is either one of two things, whether it's

an issue with the actual ports inside of the master cylinder getting clogged and making

it so you can't have enough pressure leading to your actual breaks, or if there's another

issue, it's actually probably the pushrod that goes in between the master cylinder and

the brake booster itself, the brake boosters, this big old disc-looking thing in between

your master cylinder and the firewall.

The second thing that has to do with the master cylinder but it isn't actually part of the

master cylinder, it technically has to do with the replacement of it is there's a pushrod

that's gonna be in between the brake pedal and the actual master cylinder itself, basically

inside of that brake master booster right there.

Essentially with that pushrod, it needs to be adjusted.

If for some reason you replace your master cylinder, right, because it went effective

on the inside there and you didn't adjust your pushrod that's in there, you're not gonna

have proper adjustment on your brakes.

And so what you might tend to find after you've done the brakes or done the master cylinder,

I should say, is you're either gonna have a low brake pedal where you, kind of, just

feel like you step on it, step on it before it even starts doing anything and then it

finally starts doing its job.

Or you're driving down the road and it feels as though the brakes are hanging up, more

than likely because it's over-adjusted and it's pushing that rod up against the master

cylinder plunger in there and, kind of, giving it a little bit of force already even though

you're not even stepping on the brake.

So fixes for this, of course, would be if you have an issue with the master cylinder,

go ahead and replace the master cylinder.

But when you have it off, you need to make sure that you adjust that pushrod as well.

Now, for the second problem on these engines, it comes down to the timing chain tensioner.

That's gonna be located on the passenger side rear of the engine, right back here.

It's a little bit hard to see from up on top, but if you have a mirror-like what I do, you

can see that there's a plate that has two studs and two nuts holding it on there.

It's not actually a physical plate because the tensioner is actually located inside the

engine.

This is just, kind of, the flat side of it on the outside.

As you can tell, there's a lot of oil around this one.

And this is very common.

Usually it's actually worse than this.

This one's in pretty good condition.

But with that said, the way that the timing chain tensioner is supposed to work on these

particular vehicles is with oil pressure.

If you have a leak, obviously you're gonna probably get low on oil and you're not gonna

have enough pressure.

If there isn't enough pressure, the tensioner can't do its job and you're more than likely

gonna hear a rattle noise coming from the timing chain.

Slip this up off of here, right underneath your valve cover right along here.

Obviously if this is left unfixed it's gonna cause internal damage to your engine, which

could be very costly.

1A Auto offers a kit that's gonna make sure that you can replace that for you.

It's gonna come with a seal and everything.

And aside from the kit, what I obviously would recommend to do would be an oil change as

well.

Okay.

So that's that one.

How about a third problem, right?

Let's continue on with oil pressure issues.

If you were to look at the front side of the engine right on the passenger side as well,

you're gonna your VVT solenoid right here.

It's got some wires going into it and this can tend to be an issue.

A symptom for an issue with a VVT solenoid might be something as simple as the fact that

you have an issue with the idle on your vehicle.

You have RPMs, right?

That's the revolutions per minute of your engine idling and essentially what's gonna

happen is, is the idle's gonna go up, drop down, go up, drop down, go up, drop down.

Nobody wants to feel that, especially when you're sitting at a red light and you're waiting

for it to turn green so you can get going.

With that said, there's a couple of things that we wanna look at.

One of the first things that I would do if I was trying to diagnose this issue would

be, of course, to check the oil level.

You wanna check the level and, of course, the condition itself.

I'm gonna lift it out.

I'm gonna give it a nice little wipe real quick.

This is, of course, after the vehicle's been sitting for a little while.

We wanna make sure all the oil's sitting down into the pan.

Lift it back up and we can take a look.

As you can tell, it's a little bit high right now.

It's been sitting for a period of time.

Now I'm just gonna take a nice drip and put it on a piece of paper and I wanna check that

condition.

Essentially what I'm looking for is to see if it's a nice amber color and not necessarily

a dark brown or even worse, black.

The next thing that I would wanna do is to get to this drain plug right here.

It looks as though it's a bolt just coming out of your engine, but it's not.

It's actually a plug.

And behind that plug on the inside of your engine, there's gonna be a little screen.

What tends to happen is the screen gets plugged up, especially if you don't keep up on your

maintenance/your oil changes.

So you need to take that out.

You need to make sure oil comes out and you need to, of course, get the screen out of

there and clean it up.

If you see any deposits or metal debris, you know there's an issue.

Hopefully, this is gonna help fix the issue for you.

But if it doesn't, you would need to continue with your diagnosing.

After you've went ahead and checked that screen and you verified that it was good, next thing

I wanna do is obviously close it back up and try to do an oil change, see if it runs better.

If for some reason it doesn't, the next likely candidate would be this right here, which

is your VVT solenoid.

There are a couple of tests that you can do on it which would include adding power or

ground to it to see if your engine stalls out, but that's kind of more of a diagnosis

process that will be a little bit harder to get into for this particular type of video.

And if that ended up testing fine, the next thing you need to do is get inside the engine

and check out that camshaft.

Now, the fourth problem for these particular vehicles comes down to the starter.

The starter isn't usually gonna have an issue until after 100,000 miles, but it is something

that's fairly common on these.

If you were to look underneath this right here, along the engine, you're gonna be able

to see the starter.

Also, if for some reason you do try to start your vehicle and it doesn't wanna start, you

can hear a clunk, clunk, clunk all the time from your starter every time you turn the

key, you could try to give this a couple loving bunks with maybe a hammer or a screwdriver

of some sort.

That might actually break it free to the point that you can start the vehicle and then, of

course, get yourself a brand new starter.

Now, I have a starter in my hand right here, and no, it's not the one for this particular

vehicle, but it is something that I have so I can show you.

With that said, this area right here is your starter solenoid.

Obviously if there's an issue internally there, you're not gonna be able to get power leading

down to the starter, which would, of course, shoot out this Bendix gear right there and

then turn over your engine.

If it has an issue right here, the best thing to do, of course, would be to go ahead and

replace the whole starter.

Back in the good old days, they might just replace the solenoid itself and then keep

this or even test it.

Nowadays, you can just get yourself a whole unit as a complete assembly and it's gonna

work over all the best.

What you might tend to hear before your starter actually completely goes bad is your Bendix

gear overwhelmingly making noise.

Essentially, you go to start it up, the vehicle's gonna start but you're gonna hear like a roar

afterward.

That's because this right here, the Bendix gear gets shot out because it's trying to

start up the vehicle, it goes up against either the flex plate or the flywheel, depending

on if you have an automatic or manual transmission, and then as the engine's started and running,

it's still in the outward position so it's making a whining noise until it finally retracts

back into the starter.

That noise that you're probably gonna hear is, kind of, like a precursor, letting you

know that you're gonna have an issue with the starter and then it might not obviously

work at all.

One of the first things I would check, if I was having an issue with my starter, would

be the wiring.

You wanna make sure that you don't have any green corrosion or any buildup on there that

could cause an issue with the electrical current.

Okay, friends.

So let's try to wrap this up.

Let's go for a fifth problem, right?

With that said, we're gonna talk about an EVAP system leak.

The only symptom that I would probably find for an EVAP system leak would be a check engine

light.

What that said, we obviously have to pull the code.

So if you have a nice scanner or something like that, that's gonna help lead you in the

direction you need to go.

The most common places that I would go, if I was trying to diagnose that code, would

probably be the gas cap right here.

I'm gonna start right there, pop it open, and I'm gonna take a look at this seal.

This is the most common issue.

If you happen to look at the seal and you see that it's dry, rotted, and cracked in

any way, this one actually looks pretty decent, you'd obviously want to replace this cap right

here.

Other than that, obviously, I would put this back on, you're gonna have a charcoal canister.

And that's perfect because I'm standing right where it is, except it's underneath the vehicle.

So let's take a nice little get down on the ground here.

Okay.

So when looking underneath the left rear, we can see our EVAP canister right here.

This is our charcoal canister.

It's got stuff inside there that's supposed to help with emissions.

There's a couple other things that go on with it.

You've got plenty of hoses that go to it.

If any of those are damaged or cracked in any way, that's gonna be an issue.

Of course, there's gonna be a little air filter that's attached to it as well.

It's, kind of, harder to find and usually, I believe it's up behind the fender.

If that's dirty and clogged, then, of course, it's not gonna be able to breathe properly

and you're gonna have an emissions problem.

Check all your hoses and lines that go to this.

If you wanted to disconnect them and take a peek, make sure you don't see any moisture,

or debris, or anything like that fall out of it.

Obviously that's gonna be a good thing to do.

Essentially, start with the gas cap, come down here, check all this out.

If you do continue to have an issue, more than likely it does have to do with this charcoal

canister.

Now, I know it seems like a lot of the problems that we went over in this involved the engine.

But with that said, as long as you keep up with your maintenance, the engine should last

hundreds of thousands of miles.

Okay, friends.

So that's what I've got for you for top five problems on this particular vehicle.

But since I'm standing in front of the vehicle for this, let's talk about these headlamp

assemblies.

This is super common, especially on the older Corollas like this, and essentially pretty

much every vehicle that has plastic lamp assemblies.

It's very common to happen.

It's something that you can actually service if you want it to, but usually, it's, kind

of, a temporary fix.

Overall, the best fix for this would be to, of course, replace both headlamp assemblies.

With that said, I hope you liked the video.

If you learned a little something along the way, smash on the Like button for me and leave

me a comment because I always love to hear from you.

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Thanks.