Toto Toilet Problems: How to Come up with Solutions?

Do you have Toto toilet problems? Want to flush, but it doesn’t? Is the flapper leaking and overfilling the tank? Does the toilet make strange noises when filling? Or do you have awkward smell issues?

Whatever the problem you may have – we’re going to help you fix it with this article.

Here, we talk about the 5 most common problems you may experience with a Toto toilet. And we’re going to help you fix them accordingly.

Want to know how? Then read on!

1. Toto Toilet Flapper Leaking

The first problem we’re talking about today is the Toto toilet flapper leaking. This refers to when the plastic piece on the tank that prevents water from flushing starts letting water go into the bowl without any activation.

When this happens, you’ll realize that the bowl is always filled with water, so it ends up wasting a lot of water every day.

Here’s how to check that this is happening and eventually fix it as necessary:

Open the tank of your toilet. Make sure the flapper is covering the flushing hole/valve on the bottom. Sometimes, the flapper just doesn’t reach the hole because the chain broke, or it is stuck. To fix, you’ll have to clean it. If cleaning it doesn’t fit the problem, then proceed to change the chain.

In case the flapper is covering the hole correctly, then you can proceed to pour some food coloring on the water. This will let you know if there’s any water dripping down the bowl. If you see any colored water on the bowl, then your toilet is surely leaking through the flapper.

Here, you can proceed to adjust it as necessary. When the flapper is a little loose, it starts letting water go into the bowl. Tighten it up, adjust the chain, and move it around. Get rid of any residues/dirt around the flapper as well.

Then test the toilet to see how it’s working. Pull the lever or push the button and watch whether the flapper comes back to the flushing hole/valve. If it does after flushing manually, then the problem can be the piece itself. You’ll have to replace it.

To replace a flapper, you’ll need to buy a new one first. We recommend following the same measurements as the original one (even though most flappers are the same diameter). Then proceed to change it. Start by hooking it up to the chain and then to the flapper base.

After replacing the flapper, you should test it. The toilet should be working now with no leaking at all. If it does, then you’ve successfully fixed your leaking flapper. If not, then there’s probably something more serious happening and doesn’t have much to do with the flapper.

TOTO CST243EF#01 Entrada Two-Piece Round 1.28 GPF Universal Height Toilet, Cotton White
  • Clean, modern two-piece round bowl and tank set | Toilet seat is not included
  • Product dimensions – 26-5/8” D x 14-3/8” W x 30” H | Flush valve – 3-Inch Flapper Style | Rim size – 22-7/8” D x 12” W x 16-1/8” H | Rough-In – 12” | Tank size – 7.5” D x 15-1/4” W
  • ADA, WaterSense, CALGreen, and CEC compliant
  • E-Max 1.28 GPF flushing system, creates a powerful flush
  • Universal Height for more comfort across a broader range of individuals

2. Toto Toilet Fill Valve Keeps Running

toto fill valva

When a Toto toilet fill valve keeps running, it probably means the fill valve seal is dirty, and it needs some cleaning.

Here’s how to fix this:

Start by disconnecting the water supply to the toilet. Make sure the fill valve is not getting any water flow.

Then take the fill valve cap off. This fill valve can vary depending on the type of toilet you have.

With the cap on your hands, look for any sign of dirt or deposits and clean them. This should let the valve start working as it should.

In case cleaning didn’t fix the problem, it is probably related to the flush flapper then. Here, you may need to proceed with the previous issue and repair as required (tightening, adjusting, or replacing the flapper). 

Toto MS920CEMFG#01 1.28-GPF/0.9-GPF Washlet with Integrated Toilet G400, Cotton White
  • WASHLET bidet seat toilet with integrated dual flush toilet with 3D Tornado Flush technology
  • Front and rear warm water cleanse with five adjustable temperature and pressure settings
  • The CEFIONTECT glaze and PreMist function gives the toilet bowl a lubricious quality that helps prevent waste from adhering
  • Features luxury auto open and close lid and seat with heated seat, warm air dryer, and air deodorizer for added comfort
  • Universal Height, ADA compliant, WaterSense certified, and CAL Green compliant.Trap Diameter:2-3/4 inch

3. Toto Toilet Won’t Flush

When you have a toilet that doesn’t flush, it can be because the Toto toilet leaking is not letting enough water go into the bowl.

This could be because the flushing mechanism is not working correctly, or because the fill valve is clogged or broken.

Here’s how to repair a toilet that won’t flush:

Start by checking the flapper. Open the tank of the toilet and flush. See how the flapper functions. If it opens and closes as it should – then it isn’t the problem. If it doesn’t, you may need to adjust, clean, or replace it as necessary. Replacing at once could be your best bet (unless it is new).

A fill valve that’s not letting enough water go into the tank can also be the culprit. Test the fill valve by flushing the toilet again. If you see no water coming into the tank, then the fill valve is probably clogged. Proceed to clean it as necessary. If you cleaned it and didn’t work, then replace it.

Sometimes it is not the fill valve or the flapper with the problem, but the chain/lever/button that doesn’t want to flush. You will realize this if you flush the toilet, but the tank doesn’t release any water. Then it is probably the start of the mechanism, which often means you’ll have to replace it.

In case you want to pass on testing your toilet for flushing issues and instead fix it once and for all – then you can always go to a hardware store and look for a Toto toilet repair kit. It usually contains everything from the chain to the flapper, the fill valve, and additional items necessary for the toilet to work.

This should be enough to fix the entire flush system and get your toilet working once again.

4. Toto Toilet Making Noise

A Toto toilet making noise can also be problematic, primarily when you use the toilet at night, and it starts sounding like a train inside your home.

Luckily, this is not too hard to fix either. You can follow these steps:

Start by testing the flush process. Take the lid off the tank and flush. See when the toilet starts making its sound. This usually happens after flushing, and the tank fills with water. If it starts making the noise, then lift the float ball and see if it keeps going. If it doesn’t, then it is the fill valve.

To fix this fill valve, you can proceed to replace it at once. This should save you a few minutes/hours of work. But if replacing is not an option, then you can try to fix it.

You’ll need to take the fill valve off. For that, start by turning the water flow into the tank off. Flush the system to empty the tank too.

Now you can remove the screws and the pieces keeping the fill valve attached to the toilet. Take the ball off and remove the armature. You should replace the washer on the bottom, clean the interior of the valve, and proceed to place a new washer and re-arm the valve.

Once you’ve assembled the fill valve again, then you can test it. If the sound is gone, then you’ve successfully fixed the problem. If not, you will have to replace the valve completely.

For that, you just need to unscrew the whole piece, loosen up the valve lock-nut outside, and lift the valve off the tank. Then, place the new valve on the same opening and adjust as needed. Tighten up the lock-nut.

Now you can reassemble the water-delivery system, turn on the water flow into the tank again, and test that the toilet is working without making a sound. By now, the problem should be fixed.

5. Toto Toilet Smell Problem

Last but not least, you may also be experiencing a problem with the smell of the toilet. This is also common and happens more often than people think.

Luckily, most smell problems are easy to fix. Here’s an array of smell issues you may be experiencing and a small guide on how to fix each one:

Urine Smell

If your toilet smells like urine most of the time, then it is not a toilet problem itself – but an installation or cleaning issue. Here’s how to fix it:

You will have to check whether the wax seal below the toilet is installed well enough. If it is, then you can proceed to clean the toilet.

Start by using a towel/brush with disinfectant and swipe the entire toile from top to bottom. Then check whether the smell persists. If it does, then you’ll need to reinstall the toilet and fix the wax seal below.

We recommend contacting a professional to do the reinstallation. Doing it by yourself can be costly and end up in damage to the toilet or floor.

Infected Water

Another Toto toilet troubleshooting method for smell would be to check the kind of smell you feel. If the water is infected, for example, you may get a sulfur or garbage smell instead of urine or something else.

When this happens, you’ll have to replace the plumbing system at home or eventually disinfect the drains.

Again, we recommend calling a professional to fix your infected water issue. This could be a lot more expensive than other solutions, but it is the only way to get rid of such smell.

S-Trap Problem

Sewage smell is another common problem people suffer from their Toto toilets. To fix this, it is recommended to check the P-trap or S-trap on the toilet. It could be clogged or broken.

If after checking the P-trap, you find out it is not working correctly or broken, then you may need to change the whole toilet. This will fix the problem completely.

Other issues can be a leaking P-trap, a broken seal, or clogging inside the P-trap. Calling a professional plumber can be your best bet with this type of issue as well.

Fix your Toto Toilet Now!

So, are you aware of the many Toto toilet problems you may experience? It is time to get your hands working and fix the system yourself,

Remember, if the problem is too complicated – then calling a professional is still a great idea. You will save the time and effort that fixing a toilet entails, and you won’t get your hands dirty.

Proceed as necessary, but don’t forget to check yourself beforehand. Use this article as a guide, and you will find the problem for sure!


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