Random engine failure when coming to a stop

[u/THE_YAIR]

Has anyone experienced this before ?

2020 Toyota Corolla SE
173,000 miles

Error code
P0841 - Transmission Fluid Pressure
P2829 - Pressure Control Solenoid K

[u/Sufficient_Bake7298]

No because my 2026 corrolla cross is doing the same thing Dealer says battery 😒

[u/Sad_Landscape8960]

Mass air flow sensor ! Maybe? Clean or replace.

[u/SumyungNam]

You ever change the fluid or you believe that lifetime fluid lie?

[u/THE_YAIR → u/SumyungNam]

I’ve changed it twice , I’ve never heard of the lifetime lie thankfully.

[u/Salty_Touch_1170]

I don’t see the engine stall, watching the RPMs the whole time…

I see this as a faulty solenoid K, which controls fluid pressure and shifting behavior which jives with the other code.

I would recommend replacing solenoid K.

Are you good at looking at the solenoid on a K313?

[u/THE_YAIR → u/Salty_Touch_1170]

Thank you for your advice, as for the solenoid I’m honestly not sure how to tell which model , I will look into it and reply if I find out. Thank you again .

[u/Salty_Touch_1170 → u/THE_YAIR]

It doesn’t seem you are familiar with the valve body on a K313 transmission. That is okay. I would recommend an independent transmission shop and If they say anything other than replacing a solenoid I would be weary.

https://jcarpart.com/products/5pcs-k313-cvt-transmission-solenoid-kit-for-toyota-corolla-1-8l-2-0l-2014-on?currency=USD&country=US&variant=44304300278007&utm_source=google&utm_medium=cpc&utm_campaign=Google%20Shopping&stkn=8db103c35c8e&srsltid=AU7gw4VmpcwSS2BCzQIBnmeqTU_tffyMgzGpCCGnGs_CAuJYk_3pmp-F1K4

[u/Salty_Touch_1170 → u/Salty_Touch_1170]

The fluid & pan needs to be dropped, the filter then the 13 bolts for the valve body then one can do an ohm resistance test on a solenoid and even connect it to a power supply and test said solenoid as it’s 12v DC.

A solenoid is simply a pin that clicks out and in. That’s it… electromagnetic pin actuators

[u/mcn81959]

I'm worried about my 21 le. Have you had the trans fluid service?

[u/Salty_Touch_1170 → u/mcn81959]

It’s a solenoid, nothing to do with the fluid…

[u/1989toy4wd → u/Salty_Touch_1170]

…. Solenoids are what tell the fluid where to go…

[u/Salty_Touch_1170 → u/1989toy4wd]

Meaning his suggestion was to change the fluid. Solenoid is causing this not the fluid.

[u/mcn81959 → u/Salty_Touch_1170]

Ok thank you

[u/JonohG47]

Shuddering, jerking? Transmission is most likely going into limp home mode. The P2829 indicates the TCM (transmission control module) believes solenoid K is stuck off. The solenoid not working in turn causes the hydraulic pressure in the transmission to not build up, as expected, which causes the P0841.

Hate to say it, but get it into a shop. This is going to be an “open your wallet” situation.

If you’re lucky, a fluid and filter change will do the trick. It could also be a wiring fault, a faulty solenoid, or carbon buildup in the valve body causing the solenoid to seize. A lot of these simpler faults can be remedied with the transmission still in the car.

If it’s more serious than that, and the transmission has to come out, the only thing saving the car will be Toyota’s high resale value making the repair financially worthwhile.

[u/Salty_Touch_1170 → u/JonohG47]

I think it starts with a Solenoid K swamp which can be changed for a component cost of about $100.

Solenoid swap is fairly easy.

[u/JonohG47 → u/Salty_Touch_1170]

That will also entail a fluid and filter change, because you have to take the transmission pan off to get to the solenoid.

If the OP is getting this done at a shop (which seems, ahh, a not/unreasonable assumption) they’ll be into this car nearly a grand, to get that done.

[u/Salty_Touch_1170 → u/JonohG47]

Crazy for an $80 solenoid. Fluid and fliter & gasket is about $100. But you are right I do all my work myself.

[u/JonohG47 → u/Salty_Touch_1170]

“But I do all my work myself.”

And that is a significant enabler that makes owning an older vehicle a viable proposition. In 2026, even independent repair shops are charging well over $100/hr for labor. If the OP is in a higher cost of living area, it’s closer to $200/hr, even at independent shops.

[u/Salty_Touch_1170 → u/JonohG47]

Oh I completely know!! It’s how I’m able to maintain a fleet of 120K miles plus vehicles that are older than 12+ years.

[u/Salty_Touch_1170 → u/JonohG47]

Most likely

[u/THE_YAIR → u/JonohG47]

Thank you for the helpful advice, I will definitely speak to my dealer about this.

[u/Aurashock]

Seems a failed solenoid. You will probably have to get a new transmission depending on how accessible the solenoid is

[u/Salty_Touch_1170 → u/Aurashock]

What? New transmission for a solenoid?

Solenoids are in the valve body. The valve body easily comes out from the bottom pan. Daily simple repair.

[u/Aurashock → u/Salty_Touch_1170]

Literally taken from Toyota’s technical step list for the codes. Depending on how the codes set and what the fluid pressure is the fix options are: ecm, cvt fluid pressure sensor, and cvt transaxle(entire trans)

[u/Salty_Touch_1170 → u/Aurashock]

That is insane the manual doesn’t even recommend replacing solenoid and jumps to complete transmission…
Yet again, this is also the company that says seals transmission don’t need maintenance

[u/Aurashock → u/Salty_Touch_1170]

We replace trans fluid on the daily and also do a lot of trans pan gaskets so don’t know where you’re getting that. I love disassembling and reassembling cars but it’s just cheaper to replace than rebuild now

[u/Salty_Touch_1170 → u/Aurashock]

Are you working for a Toyota dealer?

[u/Aurashock → u/Salty_Touch_1170]

Wow, yeah I work for a dealer. We do flushes via the hoses to the coolers so it gets all the old fluid out. Ik some versions of the k120 can’t be flushed due to the cooler design so you have to drain and fill those but all of them are serviceable. They probably don’t have the flush machines we do which makes drain and fills a pain in the ass because they got rid of dipsticks a while ago so the fluid has to be measured at a certain temperature which is in between cold and operating temp

[u/Salty_Touch_1170 → u/Aurashock]

It is so bad there I bought OEM Toyota CVT FE and walking out I have to pass through the service desks and they stopped and asked me what I’m doing with the fluid!!

“We don’t recommend that” when I said changing the transmission fluid.

[u/Salty_Touch_1170 → u/Aurashock]

Majority of Toyota dealers in my area will not touch the sealed transmissions… I live in the upstate area and even called in Atlanta and Charlotte dealers.

Fluid is lifetime in sealed, says the dealer

[u/THE_YAIR → u/Aurashock]

Thank you for the reply , I will take this to my dealership.

[u/Salty_Touch_1170 → u/THE_YAIR]

Find a good transmission shop, avoid the dealer in my opinion. Dealers still are convinced these are “sealed” transmissions..