2020 Toyota Corolla engine problems

ENGINE

Part is the coolant bypass valve. Toyota has been taken to court but dealership claims now that I’m over 100k miles I can’t do it. There was also a second part about 10 years but I wasn’t clear on the details of the outcome. Toyota has acknowledged this issue in court but failed to do so at the customer level in my case. engine light came on at 97k and now I’m at 104k which is over that 100k mark. Issue is I’ve only take my car to Toyota for repairs. They have known about this but failed to repair or notify me of it. I would have immediately brought my car in at 97k if. I had known. This puts not only me but my 3 kids and entire family at risk every time i drive. This is known to the dealership and they been taken to court for failures to notify customers of this known defect. It’s been inspected by Toyota the last time I took it in about a week ago at 104k miles.

NHTSA complaint #11755244 — an unverified report by a vehicle owner.

ENGINE

A message came on the screen saying “engine maintenance required” and it’s not going away. Upon doing a google search, there is a common failure in the cooling system for these cars reported by a lot of owners.

NHTSA complaint #11742614 — an unverified report by a vehicle owner.

ENGINE

The contact owns a 2020 Toyota Corolla. The contact stated that while at a red light, the vehicle shut off with the check engine and several other unknown warning lights illuminated. The vehicle restarted after several attempts. The vehicle was taken to an independent mechanic and the failure was duplicated. The mechanic retrieved DTC: P1603; "Engine Stall History" (ECM recording an unexpected engine shutdown or a communication error with the Transmission Control Module (TCM). The mechanic associated the failure with NHTSA Campaign Number: 20V682000 (Fuel System, Gasoline) and referred the contact to the dealer for assistance. Several dealers were contacted, and the contact was informed that the VIN was not included in the recall. The manufacturer was not notified of the failure. The vehicle was not repaired. The failure mileage was approximately 59,000.

NHTSA complaint #11733489 — an unverified report by a vehicle owner.

ENGINE

Car shows the below message when A/C is turned on: Engine Maintenance Required Visit Your Dealer

NHTSA complaint #11729914 — an unverified report by a vehicle owner.

ENGINE

Engine coolant bypass valve

NHTSA complaint #11707273 — an unverified report by a vehicle owner.

ENGINE

I have experienced a message saying 'Engine Maintenance Required' and after experiencing the same instances as many people have online, it seems the engine coolant bypass valve is faulty and needs to be replaced. No code can be read using a code reader either.

NHTSA complaint #11683483 — an unverified report by a vehicle owner.

ENGINE

Engine Maintenace required light came on. I was told that my coolant bypass valve needed to be replaced. This is happening on all Toyota vehicles from 2018-2024 common issue but the repair to fix something that should be covered under warranty.

NHTSA complaint #11679742 — an unverified report by a vehicle owner.

ENGINE

On June 19, 2025, I was driving and out of nowhere, there was a warning notification that said "A warning light was turned on. Would you like to call an operator?" On the digital cluster, there was a message that said "Engine Maintenance Required - Visit Your Dealer. Mileage noted down was 79,632. I asked around for some insight and people are telling me it's the water/coolant bypass valve that's leaking and the Op code is 24TE04R1. Will this be a covered service?

NHTSA complaint #11668609 — an unverified report by a vehicle owner.

ENGINE

The engine maintenance required message appeared on the dash. I was travel from work to home (about 40 miles). I pulled over immediately at a store, left my car and walked over a mile to the mechanic shop down the road (in 95° weather with a knee that has been through 3 surgeries in less than 5 years). The gentleman took me back to my car. Followed me as i took my car back to the repair shop since it was close and did not have any lights on the dash and I was not overheating. He plugged a reader in it and the error was a coolant bypass valve issue (i can't remember the exact verbage). I purchased a replacement valve 6-17-25, along with toyota coolant. I am having to wait and save up the money to have the valve replaced at the shop got the message code from. I can not afford the dealerships cost to replace the valve. The valve and coolant was expensive in itself. I have read many forums and blogs. Toyota knew there was an issue and I am requesting my reimbursement for the cost of replacing a part you knew was faulty.

NHTSA complaint #11668341 — an unverified report by a vehicle owner.

ENGINE

Flow Shut-off Valve Coolant Leak

NHTSA complaint #11665916 — an unverified report by a vehicle owner.

ENGINE

I have an error that appeared displaying “Engine Maintenance Required” after some investigation snd research, I have noticed that this is a common issue associated with the OEM Engine Coolant Bypass Valve. This occurred as I was driving home from work when I was driving down the freeway, I did not run into any obstacles or have an accident, it appeared out of thin air.

NHTSA complaint #11662682 — an unverified report by a vehicle owner.

ENGINE

unknown. i know that my car was doing fine and then randomly the coolant was low and my car was overheating on my way to work. i have yet to get it fixed, as i dont know how much it could cost me. but i read that 2020-2021 toyota makes were having issues with their coolant.

NHTSA complaint #11661991 — an unverified report by a vehicle owner.

ENGINE

An engine maintenance required warning popped up. The pop up wasn't going away. My engine sounds louder than usual when turning my A/C on.

NHTSA complaint #11661513 — an unverified report by a vehicle owner.

ENGINE

I received a "voluntary Customer Support Program" letter from Toyota saying that a small engine coolant leak can occur that "can allow coolant to drip on other parts of the vehicle. This can cause 'Engine Maintenance Required' to be displayed or cause the A/C not to function normally." Then it concludes that repair with a new "flow shut-off valve" will fix the problem, "under the terms of this Customer Support Program." I thought this was a recall and took my car in only to find that they wanted nearly $700 for the repair, because I did not have an extended warranty. When asked whether this could cause a safety problem if unfixed the reply from the Service Advisor was yes -- the coolant leak could potentially cause the engine to seize up on the highway. I was shocked that a defective part in the car I purchased new for $20,000 plus would not be replaced free of charge. I have put less than 16,000 miles on the car and now I find the resale value is essentially zero. And I now may be driving a potentially risky vehicle that could crash or leave me stranded somewhere. I feel there should be a repair at no charge.

NHTSA complaint #11659283 — an unverified report by a vehicle owner.

ENGINE

Car is currently at 56k miles and the "Engine maintenance required" popped up on my dashboard I'm pretty sure this is the engine coolant bypass valve which I read is a constant problem for new toyotas like mine

NHTSA complaint #11656924 — an unverified report by a vehicle owner.

ENGINE

Drive start control malfunction occurred when turning the car on. Second time this has happened. First time was a charcoal canister and engine coolant valve. It was replaced under warranty at 50k miles but now at 96k miles the dealer says it is not covered under the extended warranty. Not sure how this problem happened.

NHTSA complaint #11656874 — an unverified report by a vehicle owner.

ENGINE

Once I parked my car and turned on the A/C a couple mins later I received a warning message on my car screen saying “ Engine Maintenance Required Visit Your Dealer”. After having my car for 4 years I’ve never received this message till now (04/22/25). I thought it was because I needed an oil change but I was wrong because my oil is good. I checked my car and saw that the issue is the “coolant bypass valve”. I don’t even use my car that much for this to happen. I saw this is a common issue with a Toyota Corolla 2020 but the dealership does not want to fix this issue for free.

NHTSA complaint #11656209 — an unverified report by a vehicle owner.

ENGINE

I own a 2020 Toyota Corolla, and without any prior warning, the “Engine Maintenance Required” message appeared on my dashboard at approximately 79,575 miles. There were no unusual symptoms—no overheating, strange noises, or performance issues—before the light turned on. I had my vehicle inspected by Golling Toyota of Warren, where they diagnosed the issue as a faulty Engine Coolant Bypass Valve. I was informed that the valve needed to be replaced and flushed. The total cost of the repair was $932.21, which I had to pay out of pocket. Because the message specifically said “Engine Maintenance Required,” I was concerned that it could be a serious engine issue. Out of caution, I avoided driving the vehicle until it was inspected, as I didn’t know whether it could result in engine damage, performance failure, or a sudden breakdown while on the road. The fear of an unknown engine-related malfunction created a genuine safety concern for me and others —especially since the warning came without any prior symptoms. I later learned that the problem was tied to the Engine Coolant Bypass Valve, which is known to fail prematurely in Toyota vehicles. This failure can affect engine performance and temperature regulation, increasing the risk of engine damage or failure while driving. There is already a class-action lawsuit concerning this issue, yet Toyota has not issued a recall. Owners like myself are being left to pay out of pocket for a known defect that poses real safety risks. I’m submitting this complaint in hopes that Toyota will be held accountable and that the NHTSA will take appropriate action to protect consumers from this recurring and potentially dangerous defect.

NHTSA complaint #11652732 — an unverified report by a vehicle owner.

ENGINE

“Engine maintenance required” alert received, related to a faulty coolant bypass valve which will need replacement. Vehicle is currently at 51,049 miles. Alert message can’t be dismissed from the dashboard. It obstructs a significant portion of the speedometer.

NHTSA complaint #11650700 — an unverified report by a vehicle owner.

ENGINE

Coolant bypass valve broken dealers are charging $800, class action lawsuit pending

NHTSA complaint #11648474 — an unverified report by a vehicle owner.

ENGINE

Engine Maintenance Required displays see dealer displays in Panel. I have taken to my local shop Engine coolant bypass valve replaced. Still having same issue.

NHTSA complaint #11646807 — an unverified report by a vehicle owner.

ENGINE

Valve matic is messed up. According to my research this is a known issue with 2020 Toyota corollas.

NHTSA complaint #11640312 — an unverified report by a vehicle owner.

ENGINE

Vehicle maintenance light won’t turn off, stays off if car started with AC off but comes on and stays on while AC is running. Coolant overflow valve malfunction

NHTSA complaint #11638624 — an unverified report by a vehicle owner.

ENGINE

"Engine maintenance required. Visit dealer" message appeared about 2 years ago. The message appears when I turn on the A/C or heater and will not go away, which affects multiple functions such as speedometer and text function.

NHTSA complaint #11635525 — an unverified report by a vehicle owner.

ENGINE

Engine coolant leak from an issue with a valve that allows coolant to drip on other parts of the vehicle. “Engine Maintenance Required” is displayed on the instrument cluster and causes the A/C to not function normally.

NHTSA complaint #11635351 — an unverified report by a vehicle owner.

ENGINE

I keep getting a warning sign on my dashboard stating that "Engine maintenance required. Call your dealership". After scanning for codes, I get the code P2681, or that the Engine coolant bypass valve is faulty. After looking online it appears that this is a common issue with this car model. There is a class action lawsuit for this right now since the part is known to be faulty and can crack and leak engine coolant. Toyota has refused to issue a recall for this and will charge you to replace this faulty hardware. I also am not able to clear the message while driving and it will constantly pop back up distracting me while driving and making me unable to see any important warning on my dashboard. This is endangering my ability to safely drive my vehicle.

NHTSA complaint #11634457 — an unverified report by a vehicle owner.

ENGINE

There was a maintenance required notice on my dashboard and I searched up that it was my coolant bypass valve having an issue. Apparently it’s a defective part in Toyota Corolla and rav4 models from 2019-2023 I believe. The notice would come on and off each time I would start the vehicle. The dealership has confirmed this issue is common and after having it inspected and diagnosed, it was indeed the coolant bypass valve. My safety and the safety of others were fine, my engine would’ve been the unfortunate casualty if I did not take care of this.

NHTSA complaint #11631190 — an unverified report by a vehicle owner.

ENGINE

Car would not start/turn over - Not battery related. Toyota determined the ECU went bad and stated the cause was improperly jumping the battery. The issue happened randomly one day (car was driving fine previous days)

NHTSA complaint #11626370 — an unverified report by a vehicle owner.

ENGINE

There is a problem with the bypass control heater valve of my car Corolla Toyota 2020 It says i have to replace it but it's still running good. I research what this part is about and it says that this is a malfunction in all the Toyota Corollas and RAV4 2019-2021. The message "engine maintenance required" doesn't go away and it doesn't let me see the mile percentage when driving. This problem has been confirmed by a mechanic who installed the tablet and run a test to see what's wrong with it. The car has not been checked by insurance because of this manufacturer malfunction. This all started happening 6 months ago and haven't found a way to replace it and dealership charges over 800 dollars for a mistake Toyota made on all Corollas line. Please help me find a solution. Thank you!

NHTSA complaint #11625521 — an unverified report by a vehicle owner.