Source
r/COROLLA•
SpacemanSpiff23

My ‘21 manual went into Low Power Mode while accelerating onto the highway. Is this a common thing, or did I break something?

I was getting on the highway, the car was pretty warmed up from maybe 40 minutes of driving, so it wasn’t a cold engine. I decided to leave it in 3rd and give it some revs. I got to about 5500, definitely didn’t redline it or hit the limiter, but right when I was about to go to 4th, it felt like I just took my foot off the gas. Low power mode and check engine light came on.

I was about 3 miles from the dealership, so instead of stopping on a sketchy stretch of highway, I limped it to the dealer. They said it’s going to be a couple days before they can look at it.

Does it sound like I killed the car? Or is this something that happens?

Posted Jun 19, 2023, 1:41 AM UTC

410
LeonChestnut•

Can't say for sure, I'm not a mechanic. Low power mode is the car trying to prevent damage to itself, so something is not right. Hopefully it's nothing too expensive & I wish you luck.

4
SpacemanSpiff23OP•

Thanks. The drivetrain is still under warranty, so hopefully it doesn’t cost me anything.

2
LeonChestnut•

hey good news. i'll keep my fingers crossed for ya

2
SpacemanSpiff23OP•

1 spark plug was completely worn out and failed. Other 3 were fine. Mechanic had never seen anything like it. Spark plugs are “wear items” so not covered. Cost me $400.

2
LeonChestnut•

Thanks for the follow up. How many miles on your car?

1
drake90001•

$400 for a spark plug? Jesus

1
darnoth•

Sometimes the computers go into safe mode and it could freak you out. It happened to me while I was going about 75 on the highway on a really hot Texas day. I think the cooling system triggered something in the computer. So I replaced thermostat, coolant temp sensor, coolant flush,, and water pump. The car needed some cooling system maintenence. But of course this was on a 160k mile corolla, so I'm not sure in your particular case. I'd probably check your spark plugs/ coils and make sure everything is tightened down. Check your cooling system,, make sure everything is good to go. Those coolant temp sensors are easy to break. Also even evap components or a loose gas cap can trigger the ecu to go into limp mode as well. Maybe take advantage of your warranty while you still have it.

1