How much damage could I have done?

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Hopefully someone gets a good laugh out of this… I have a brand new 2022 4Runner and read about how vehicles that have flood mode will allow the starter to turn the engine at a low rpm to circulate oil through the motor. I decided to try this without verifying that my car had this feature. I had driven about 5 miles to the grocery store so the engine was warmed up and lubricated. I went inside and returned to my 4Runner about 10 minutes later. I pressed the brake and gas to the floor and held the start button expecting the engine to turn over at the speed of the starter and instead the car started and revved to about 5k rpm. I immediately released the gas. I’m assuming that since the car was driven a few miles prior and only sat for 10 minutes that there would have been enough of an oil film to protect the engine for the brief moment that the engine saw 5k rpm. Am I worried about nothing or is it possible I could have a premature engine failure due to my idiocy?
 
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Now you know.

It didn’t hurt anything. I wouldn’t keep trying it though. Not sure what they mean by flood mode.

Certain cars have the ecu programmed that if you hold the pedal to the rug and crank it it cranks with the injectors disabled. RX8's are one that come to mind. They liked to flood the motor and foul the plugs if you start them for a short time and shut them off. I think Honda's will do it as well. I'm sure there's others. Also useful for certain diagnostics.
 

Jmcgrady1994

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Thanks for the responses all, helped put my mind at ease. These 4.0 motors in 4Runners are noisy to begin with so you can imagine how paranoid I was on the ride home.
 
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I’ve heard of flood mode and have it on the Seadoo, hold the throttle and crack it to distribute fogging oil at the end of the season and it won’t start but never tried it on a automobile. Agreed with others you’re fine, just don’t make it a habit.
 
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Hopefully someone gets a good laugh out of this… I have a brand new 2022 4Runner and read about how vehicles that have flood mode will allow the starter to turn the engine at a low rpm to circulate oil through the motor. I decided to try this without verifying that my car had this feature. I had driven about 5 miles to the grocery store so the engine was warmed up and lubricated. I went inside and returned to my 4Runner about 10 minutes later. I pressed the brake and gas to the floor and held the start button expecting the engine to turn over at the speed of the starter and instead the car started and revved to about 5k rpm. I immediately released the gas. I’m assuming that since the car was driven a few miles prior and only sat for 10 minutes that there would have been enough of an oil film to protect the engine for the brief moment that the engine saw 5k rpm. Am I worried about nothing or is it possible I could have a premature engine failure due to my idiocy?
No damage, only potential for damage is if the engine is ice cold (ie below freezing startup after sitting 6+ hours). I spent almost two hours yesterday trying to (unsuccessfully) get unstuck in snow with bursts at 6500rpm. Engine got hot enough the fan was still running when I shut it off. I've done stuff like that dozens of times with no problem. If your engine is healthy and full with relatively clean oil don't be scared to give it full beans.
 
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Certain cars have the ecu programmed that if you hold the pedal to the rug and crank it it cranks with the injectors disabled. RX8's are one that come to mind. They liked to flood the motor and foul the plugs if you start them for a short time and shut them off. I think Honda's will do it as well. I'm sure there's others. Also useful for certain diagnostics.


Thanks. I just haven’t heard of anyone flooding a engine since injectors came into play.
 
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Wats the point in asking? Damage is done, or not. Are you going to do a tare down if enough folks tell you it's toast?
 
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I did the same thing once on my previous 2006 Accord. I was also worried but I never had an issue after that incident. Having said that it's not something you should do on a regular basis.
 
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Wats the point in asking? Damage is done, or not. Are you going to do a tare down if enough folks tell you it's toast?
Same applies with cutting open oil filters and finding how horrible it looks or was constructed .... after it's been used in the engine for thousands of miles. :ROFLMAO:
 
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Bill_W is right.

On most car that I know of, you have to go past 80% throttle in order for flood mode to work.

It sounds like to me that Jmcgrady1994 probably didn't push the pedal all the way down. I've done that too.

Using flood mode right after an oil change, or after the car sat for a couple days is good, but other than these instances, it's really unnecessary to flood mode the car, especially in a 2022 4Runner that uses 0w20.

0w20 doesn't get as thick when the engine cools compared to 5w20, so flood mode is unnecessary, but doing it won't harm your engine.

Just make sure you use 0w20 for the best cold engine protection and hot engine prote. You don't need to flood mode.
 

Jmcgrady1994

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I did the same thing once on my previous 2006 Accord. I was also worried but I never had an issue after that incident. Having said that it's not something you should do on a regular basis.
Thanks, that puts my mind at ease! I don’t plan to ever do it again.
Bill_W is right.

On most car that I know of, you have to go past 80% throttle in order for flood mode to work.

It sounds like to me that Jmcgrady1994 probably didn't push the pedal all the way down. I've done that too.

Using flood mode right after an oil change, or after the car sat for a couple days is good, but other than these instances, it's really unnecessary to flood mode the car, especially in a 2022 4Runner that uses 0w20.

0w20 doesn't get as thick when the engine cools compared to 5w20, so flood mode is unnecessary, but doing it won't harm your engine.

Just make sure you use 0w20 for the best cold engine protection and hot engine prote. You don't need to flood mode.
Thanks for the reply! It’s possible that I didn’t have the throttle all the way down. Since it’s a push button start, I also assumed the gas and brake needed to be pressed to the floor. That may have also been a factor too, maybe the gas only needed to be pressed to the floor. Anyway, it doesn’t really matter since I won’t be trying that again! After your explanation of 0w20 oil, I don’t think it’s necessary to ever need to utilize flood mode.
No damage, only potential for damage is if the engine is ice cold (ie below freezing startup after sitting 6+ hours). I spent almost two hours yesterday trying to (unsuccessfully) get unstuck in snow with bursts at 6500rpm. Engine got hot enough the fan was still running when I shut it off. I've done stuff like that dozens of times with no problem. If your engine is healthy and full with relatively clean oil don't be scared to give it full beans.
Gotcha, I couldn’t find an answer for how long the oil will leave a film on the internal parts after shutting down an engine but I’m assuming it’s longer than 10 minutes (more like 6+ hours like you stated). I changed my oil early at 1000 miles so it’s pretty fresh and my car takes just over 6 quarts so it was full. I immediately thought of the videos I’ve seen of people giving full throttle when off-roading trying to get up a hill or get out of a rut and figured if they could give it the beans like that then I hope I would be fine too.
 
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The OP said he had the gas pedal to the floor, not sure why some of you are doubting that.

In all honesty clear flood mode is no longer a necessary feature in fuel injected engines. Fuel injected engines don’t just flood the cylinders with gasoline unless a one of the injectors has a stuck needle. The only time clear flood mode may be useful is in the event a vehicle fails to start in very cold weather and the cylinders end up being flooded with fuel. Fuel injection calculations are so precise now that rarely does a vehicle not start in cold weather. Some vehicles don’t even utilize a clear flood mode because it’s such a rare occurrence in todays age. On those vehicles you need a high level scan tool to put the vehicle in a diagnostic mode to disable the fuel injectors. Ford and Honda both operate this way now in some vehicles. The diagnostic mode is mainly used for cylinder compression testing more than anything else.
 
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Thanks, that puts my mind at ease! I don’t plan to ever do it again.

Thanks for the reply! It’s possible that I didn’t have the throttle all the way down. Since it’s a push button start, I also assumed the gas and brake needed to be pressed to the floor. That may have also been a factor too, maybe the gas only needed to be pressed to the floor. Anyway, it doesn’t really matter since I won’t be trying that again! After your explanation of 0w20 oil, I don’t think it’s necessary to ever need to utilize flood mode.

Gotcha, I couldn’t find an answer for how long the oil will leave a film on the internal parts after shutting down an engine but I’m assuming it’s longer than 10 minutes (more like 6+ hours like you stated). I changed my oil early at 1000 miles so it’s pretty fresh and my car takes just over 6 quarts so it was full. I immediately thought of the videos I’ve seen of people giving full throttle when off-roading trying to get up a hill or get out of a rut and figured if they could give it the beans like that then I hope I would be fine too.
It's not just about oil film it's also about operating temperature and the tight clearances at those temperatures. A cold engine is looser, and an ice cold engine might hit oil pump bypass above 4k RPM, extreme cold with very thick oil (like a 15w-40 or 20w-50) could also result in the oil pump drive breaking off. Most antiwear additives also don't work below 150°F, especially zddp. Even in the extreme cold we've been having up north it takes several hours of the engine being off for the coolant temperature gauge to drop to the bottom, and 8 hours for it to completely drop to ambient temperature.
 
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