Smell inside my dishwasher - HELP!
 

I don’t know what to do next. I’ve a horrible smell coming from my dishwasher, so bad it lingers for some time. Don’t suggest rinsing off the dishes before putting them in there, washing off the filter, checking the pipes etc . . . We’ve done it all.

We’ve had a plumber to install a new sink and she checked all the pipes. I asked her specifically about the problem and she just shook her shoulders.

The dishwasher was brand new in August of 2024 and it’s been smelling since then. I bought a bottle of dishwasher cleaner and that didn’t help. I mean this smell is so bad it’ll make you sick!

Today I called the company that made it and she said they would have someone contact me.

In the meantime, I thought I would put it out to all of you - do you know anything that might help?

Have you cleaned the drain filter at the bottom of the dishwasher? It catches the larger pieces of food and if not cleaned regularly that food will begin to rot.

Sounds like you had a "Plumber's Helper" install your sink and your dishwasher was not properly plumbed back into the sink drain. Common issue when your sink is replaced and Plumber is lazy.

You might check:

- Grime (of some sort) on door seals, particularly on bottom of door in a hard-to-see spot
- Clean filter as previously suggested
- Look for signs of a water leak underneath the washer
- Try cleaning with something like Finish Dishwasher Cleaner (maybe this is what you already did)

Four months seems like a short time to have a problem but maybe about right for a small leak underneath to start to smell.

Whatever it turns out to be, please post it here so we all know what to look for if it happens to us.

Im curious then where else they would drain it to? It sounds like the smoking gun but if dirty water is laying in the pipe would it not have been flushed out when she ran the cleaner through it?

A dishwasher connected to the sink should have a "high loop" or an "air gap".

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One possible cause could be a lack of "high loop" between the sink and dishwasher. That is a pure guess, but worth a check.

The drain line connecting the sink drain to the dishwasher needs to run from the sink drain first up high to above the bottom of the sink then down to the dishwasher. If this "high loop" is not present, then the stuff put down the sink drain can go into the dishwasher. where it will rot and smell, particularly if you don't run your dishwasher very often.

As I said, that is just a stab in the dark. But I did have that problem in my villages house.

OP, previous replies appear to have hit all of the probably causes for the odor. You may need to look at the instruction manual for the location and how to remove and clean the filter, ours a Whirlpool is real simple, some others not so simple. Also, look at the heater coil (if you use the heated dry option) and see if there is anything trapped to melted in this location.

Lemi Shine Natural Dishwasher Cleaner
 

I use this once a month. It works for me. Amazon.com

sounds like a vent problem , the bad smell comes from the sewer piping maybe not hooked up.

Was the smell there before the new sink installed? Also, a neighbor had new counter tops and sink installed, the air vent was in the way and had to be moved, there are specific requirements for how this device is installed, so have a qualified licensed plumber check it out.

It depends on the smell.
Tinker - plastic on heated coil - burning plastic odor
Dreamer - sewer smell - sour odor
Brian - high loop - rotting/grease odor

Would be interested to know the culprit. That sour odor from sewer line can easily rise back up through an improper plumb or a empty/dry p-trap. Especially if your HVAC system is circulating air, it will pull air through the p-trap, but it's obvious. It's a tangy sour smell almost like rotten eggs. Sulfuric nose twitcher.

You stated a new sink was recently installed...
Is the dishwasher drain connected to the sink waste piping before or after the "P" trap. If after the trap, you are getting sewage smells because there is nothing to stop gases entering the home... DEADLY !!

I would rule out the DW as being the culprit. Clean the filter at the bottom - most likely a Youtube video out there for your make/model. Then run a hot cycle with one cup of vinegar (leave it in the cup on top rack), follow with a short cycle with 1/2 cup of backing soda sprinkled on bottom. If still smelly - I think the suggestion of the plumber doing a poor job may be the issue. Good luck!

Could be your disposal because they harbor decaying food. Try using a foaming disposal cleaner. Also, run the hot water for 30 seconds in the sink with soap, then run the disposal before you start the dishwasher.

Sounds like she had this issue before the sink replacement because she asked the plumber while he was there, and she wouldn’t be using the dishwasher when everything was disconnected while replacing the sink.

Check the filter, sounds like you haven’t cleaned it out before.
Maybe something plastic fell on the heater core and melted.
Check the vent filter on the pipes underneath your sink, replace it if you haven’t replaced it for a few years.

1-1/2 in. or 2 in. PVC Mini Vent Air Admittance Valve

Does the bad smell only come from the dishwasher (ie only when you open the dish washer). Or does it come from the general area of the dishwasher? If it’s the latter it may be from a faulty air admittance valve allowing sewer gas to enter your home. Another possibility could be the p-trap is being sucked dry due to improper plumbing , which might suggest you need an air admittance valve. Just a thought!

Is it possible a small animal got under the dishwasher and died? When we replumbed our utility room sink we ended up with two frogs in the house...

I always prewash my dishes so no chunks. I also add some baking soda and vinegar every now and then.

When my dishwasher smells which happens from time to time I pour bleach right inside and then run it. I don’t measure but it was about a half cup. Works every time.

👍👍👍👍👍

sprinkle baking soda on the bottom of the dishwasher and place 1 cup vinegar on the top shelf. run reg cycle. also make sure no mold on inside door near gaskets.

I have exactly the same problem. Done all you have done & had a plumber take a look who almost got sick from the smell. Only thing I have found is to leave the door open just a bit preventing whatever it is from being sealed inside the dishwasher. Lmk if you find a solution. Good luck

I know what you are talking about. You must have a KitchenAid. I have been dealing with this issue for some time. For me nothing has solved the problem and KitchenAid is no help. Good luck!

I question if you have sewer gas backing in. Is your dishwasher connected above the sink P trap? If not that's your issue.

Cleaning tablets
 

I had the same issue. I used the tablets you can buy to clean the dishwasher. Drop tablet in washer and run a cycle. Smells good now. There are tablets for your clothes washer too. Look in the aisle with cleaning products. Come in a small box usually with 4 or 6 tablets. Remember when shopping to look at top and bottom shelves.....amazing the stuff you find. To keep your stainless appliances "sparkling", wipe with baby oil.

Check the drain filter for something stuck. Also you can a run a cleaning cycle on sterilize (Very Hot Water) and this might help.

Your Plumber was unqualified, lackadaisical and had a poor attitude. Any competent Plumber would have diagnosed and repaired the issue.

Have you cleaned out the filter? Should be located in bottom. It twists out.

Is it possible that a little critter (mouse) died somewhere inside the dishwasher prior to you purchasing it, and the odor is noticed when it’s been used?

If something was stuck in the drain hose then the dishwasher wouldn’t drain.

We’ve had two plumbers out and they both said the same thing.

We’ve pulled out the dishwasher and looked all over. But one thing we noticed when we did that is our dishwasher has an awful lot of small areas that hold water.

I called the home service the maker said would be coming out and she said “they don’t fix that kind of thing. Better to call Bosch back.” So I did and they hooked me up with a company that only comes out to TV on Thursday. I have an appointment on the 30th.

Lets us know as my disposal stinks like your dishwasher, but its all installed properly, and i flush it, put lemon rinds down it, other things, to it as well

Have you taken some paper towels and wiped the underside of the rubber thingy at the top? Gross, but needs to be done.
A tip I learned from a friend...When I make something in my blender, I clean it by rinsing it out and blending a squirt of Dawn and water. I start the disposal and pour all that down at once.

You know they never found Jimmy Hoffa

We have an 800 series Bosch(one of their best) also. Also had a smell. Does require a very thorough cleaning of the gray colored filter every couple of months. It does get very nasty

Lots of good suggestion on the thread about cleaning the strainer on the DW. I had a similar experience when I changed my bathroom sinks. Not sure why changing the sink made the problem appear, but it did. When I ran the water in the sink, I got an awful sewer type smell. Called a friend of mine who was once a plumber, and then became an engineer. He told me it was biofilm in the drain pipe. I removed the p trap and other plastic drain pipe from the sink to the wall, and indeed there was biofilm attached to the inside wall of the pipes. I could smell the odor coming from the removed biofilm, and was confident that was the source. Biofilm is very stick stuff. I had to run a rag thru the piping to remove the biofilm. There are chemical biofilm removers, not sure how effective they would be. You really need physical (not chemical) removal of the biofilm. Put the drain pipes together and the smell was gone. If you can't do it yourself, I highly recommend that you have a plumber do it. It's not that difficult of a job, the drain pipes just screw together, no soldering required.

Gasp! My psy-chic predicted he'd be found in a village in central Florida. O. M. G! 😱