A bad timing belt or timing chain can be a serious issue. If it jumps a tooth or breaks entirely, it can lead to permanent engine damage. Knowing the symptoms of a bad timing belt or chain is vital so this doesn’t happen to your Toyota Fortuner.
Timing belts are made out of rubber and nylon, unlike a timing chain, which looks much like a bicycle chain. Here’s more on a timing chain vs. a timing belt. No matter which one your Fortuner has, the symptoms are the same when they fail.
Here are some of the most common warning signs of a bad timing belt on the Toyota Fortuner:
1. Engine Won’t Start
If your Fortuner’s timing chain or belt has fallen off completely, broken, or has jumped a few teeth, it is entirely possible that the engine won’t even start.
You might hear it slapping around (broken timing belt or chain) as the engine cranks over. If this is the case, the damage is already done.
2. Slapping Noise
A good indication that a timing belt has gone bad is going to be noise. There may be a sound of rubber beating against something. It’ll typically be a rough rattling sound, and it is often most noticeable right when you start up your Fortuner.
3. Performance Decrease
If the timing belt has jumped a few teeth, but hasn’t fallen or broken off yet, it can knock the engine out of time. The timing belt is responsible for keeping the camshaft(s) in sync with the crankshaft.
If the timing belt has shifted, it causes the valves to open and close improperly, leading to diminished performance.
4. Loss of Fuel Mileage
Fuel mileage will suffer when engine timing is off. A misaligned timing belt will cause a decrease in fuel efficiency due to the engine working harder than it needs to be.
5. Glazing and Dry-rot (Timing Belt Only)
If you are looking at the Fortuner’s timing belt itself, check to see if the belt is glossy. It should grip your finger as you lightly brush across it. If it is slippery and dry, that is a great indication it could be bad as well.
6. Check Engine Light
If the timing chain or belt needs replaced due to wear, but hasn’t jumped a tooth, the service engine soon light will not come on. But, if it has jumped, the check engine light will very likely come on. At the least, you should get some sort of misfire relate codes.7. Other Signs of a Failing Timing Belt
Here are some other signs of a failing timing belt or chain:
- Metal shavings in the oil
- Ticking noise coming from the cylinder head area
- Low oil pressure
- Excessive vibration in the engine bay (Due to an engine misfire)
How to Diagnose and Fix
Check for Codes
If your Fortuner’s check engine light is on, start your diagnosis there. Modern engines use a crank and camshaft sensor to verify that they are spinning together.
If you pull P0016 (Crankshaft Coerlation) or P0017, that is a strong indication that the engine timing is off.
Replace the Timing Belt or Chain
Replacing a timing chain is not easy and requires considerable knowledge of the engine and its components. It is best done by a trained professional with access to specialized tools.
Replacing your Toyota Fortuner’s timing chain can be expensive as it often involves several hours of labor from experienced mechanics.
Because the timing chain is essential to the engine’s operation, mistakes made during installation or adjustment can cause serious problems.
An incorrectly installed or adjusted timing chain can cause catastrophic damage, resulting in costly repairs and replacements that could have been avoided.
For these reasons, if you suspect your Fortuner’s timing chain needs replacement, contacting a certified professional who can safely perform the job is highly recommended.
Don’t Overlook the Tensioner
A timing belt tensioner maintains the correct tension on the Fortuner’s timing chain. This ensures your vehicle’s engine runs smoothly and the timing chain remains in place.
If the tensioner is not functioning correctly, it can cause damage to the engine since it will be unable to keep the timing chain properly secured.
Therefore, if you are having your timing chain replaced, make sure that the tensioner is checked and replaced if necessary. This will help to ensure that you don’t have any future problems with your vehicle.
The timing tensioner can also fail. The tensioner’s job is to keep the right amount of pressure on your Toyota Fortuner’s timing belt or chain.
As the belt/chain stretches through regular operation, it gets loose and falls off or jumps. The tensioner keeps this from happening by maintaining consistent force on the belt. So, as the belt stretches, it adjusts for this stretching.
If the tensioner is no longer keeping enough pressure on the timing belt, it’ll cause it to fail.
If you are going to replace your TacomA’S tensioner, swap the belt as well. It’s hard to get to, and timing belts/chains are relatively affordable. It’s just the TIME that it would take you or your mechanic to get to it that’s the problem.
Conclusion
The timing chain is an important component in a Toyota Fortuner’s engine, and it needs to be properly maintained in order for the engine to run smoothly and efficiently. If the timing chain fails, your vehicle may suffer from major damage or even break down completely.
Timing belts are rare. You’ll likely find a timing chain in most cars and trucks. Smaller cars, particularly Japanese-made ones, can use timing belts instead of a timing chain. They are most commonly found on four-cylinder engines.
Most manufacturers will recommend changing the timing belt at 60k or 100k miles. There isn’t always a service window for the chains, although it can vary.
Many people get into trouble when they buy a used car with 100k, not realizing that the belt service will be immediately due.
Good luck with your Fortuner. If there is anything that you would like to add, please leave a comment below. We would appreciate it.