How much damage could I have done?

Jmcgrady1994

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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.
Thanks for the explanation! I imagine my engine temperature was still above 150F when I restarted the car and the rpm’s went to 5k. Lesson learned and hopefully I’ll forget all about it by the time my 4Runner hits 200k miles :)
 
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Thanks for the explanation! I imagine my engine temperature was still above 150F when I restarted the car and the rpm’s went to 5k. Lesson learned and hopefully I’ll forget all about it by the time my 4Runner hits 200k miles :)
At that temperature there is zero practical problem regarding the oil.
 
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Back in the day, when engines had carburetors, those were typically installed at the vehicle assembly plant. The engine manufacturing plant hot tested their production engines coming off the line with a setup that used propane fogged into the intake manifold. Some lines would take it right up to 5000 rpm and if nothing blew up, it was good to ship.
 
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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.
Boron is one anti wear that works below 150 f.
 
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Flood mode has nothing to do with gas or injectors .
Purpose of it is is to pressurize the oiling system. On Ford vehicles push the gas pedal all the way to the floor , turn the engine over let go of the gas pedal engine will start.
 

ZeeOSix

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Flood mode has nothing to do with gas or injectors .
Purpose of it is is to pressurize the oiling system. On Ford vehicles push the gas pedal all the way to the floor , turn the engine over let go of the gas pedal engine will start.
It's also used for a flooded engine. What gets a flooded engine to start easier is get as much air into the cylinders (ie, WOT) while cutting off all the fuel. Even carburated engines will start easier if flooded if the throttle is held wide open to get as much air into the cylinders as possible.
 
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Flood mode has nothing to do with gas or injectors .
Purpose of it is is to pressurize the oiling system. On Ford vehicles push the gas pedal all the way to the floor , turn the engine over let go of the gas pedal engine will start.
Clear flood mode is the actual term that manufacturers used and it is intended to clear out any fuel flooded cylinders by disabling the fuel injectors.
 

Jmcgrady1994

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Having accidentally floored my 4Runner last summer on a cold start, and it still runs fine and doesn't burn any oil, you will be OK.
Really appreciate your input! I actually did some math to try and put my mind at ease and my engine would have seen wear equivalent to that of a start up directly after an oil change without pre-filling the oil filter. Assuming it takes a few seconds for the oil pump to fill the oil filter housing and start building pressure.
 
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Really appreciate your input! I actually did some math to try and put my mind at ease and my engine would have seen wear equivalent to that of a start up directly after an oil change without pre-filling the oil filter. Assuming it takes a few seconds for the oil pump to fill the oil filter housing and start building pressure.
I’d love to see that math.
 

Jmcgrady1994

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I’d love to see that math.
It was too complicated for me to figure out how many revolutions my engine made within the 1 second that it started and revved to 5k rpm so I just went worst case scenario and assumed 5k rpm for 1 second which equates to roughly 85 rotations of the crankshaft. I’m also assuming that the engine revved to 5k rpm with little to no oil pressure.

I compared that to the 4 seconds or so it would take for the engine to build oil pressure in the event that I changed the oil and didn’t pre-fill the oil filter. This is debatable still but many people change their oil and never pre fill the filter and never experience issues. I got the 4 seconds from a thread here where someone monitored oil pressure on a scan tool and compared how long it took to start building oil pressure when the oil filter was prefilled and when it was dry.

My idle is 1500 rpm at start up so that equates to 25 rotations per second and over 4 seconds of no oil pressure, that equates to 100 rotations.

So essentially I saw about the same amount of rotations of the engine while it had little to no oil pressure as if I had done an oil change and started the motor without pre filling the oil filter.
 
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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.

F150s right through 2021 have "flood mode". Pretty sure all fords with fuel injection are the same:

 

ZeeOSix

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It was too complicated for me to figure out how many revolutions my engine made within the 1 second that it started and revved to 5k rpm so I just went worst case scenario and assumed 5k rpm for 1 second which equates to roughly 85 rotations of the crankshaft. I’m also assuming that the engine revved to 5k rpm with little to no oil pressure..
Since you did this a short time after engine shutdown, I'd say the oiling system (all the galleries) were still full of oil (unless the filter ADBV is totally bad, which I doubt it was) and therefore within a few RPM oil was flowing to all parts the oiling system supplies. You don't have to have full oil pressure to have flow and supply of oil. Plus, all the journal bearings had a nice film of oil on them. You're over thinking it and worrying too much.
 
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Ford and Honda both operate this way now in some vehicles.
F150s right through 2021 have "flood mode". Pretty sure all fords with fuel injection are the same:

Notice how I said “in some vehicles”.

Manufacturers have been talking away “clear flood mode” capability as the years progress. Modern fuel injection systems don’t use failure prone fuel pressure regulators anyone, which were one of the main reasons for engine flooding, hence no real need for clear flood mode.
 
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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.
And here I feel guilty when my F250 downshifts on cruise while pulling a hill and hits 3000 rpm. It’s a 6.2l
 
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I did that once on the Cherokee when I changed it's oil for the first time. I thought it had a clear flood mode. It did not.

And here I feel guilty when my F250 downshifts on cruise while pulling a hill and hits 3000 rpm. It’s a 6.2l

I used to feel bad about spinning my 2 valve 5.4 that fast while towing. Once I learned that it likes to eat, towing is a lot more pleasant. It seems to like minutes on end at 4500 while towing up a hill. The right side exhaust manifold doesn't feel the same way.
 

Jmcgrady1994

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I did that once on the Cherokee when I changed it's oil for the first time. I thought it had a clear flood mode. It did not.
Did you have any issues pop up down the road?
Since you did this a short time after engine shutdown, I'd say the oiling system (all the galleries) were still full of oil (unless the filter ADBV is totally bad, which I doubt it was) and therefore within a few RPM oil was flowing to all parts the oiling system supplies. You don't have to have full oil pressure to have flow and supply of oil. Plus, all the journal bearings had a nice film of oil on them. You're over thinking it and worrying too much.
Thank you for the reply. Makes sense, and I agree. I am totally over thinking it. This is the first new car I’ve ever owned so I’m a little paranoid about possibly damaging something. I’ll continue to drive on and try not to think about it. I’m sure a few months down the road I’ll have forgotten all about it
 
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Did you have any issues pop up down the road?

Thank you for the reply. Makes sense, and I agree. I am totally over thinking it. This is the first new car I’ve ever owned so I’m a little paranoid about possibly damaging something. I’ll continue to drive on and try not to think about it. I’m sure a few months down the road I’ll have forgotten all about it

Nothing's made itself apparent. That was at 95000 miles and it just rolled over 215000 miles 12 years later.
 
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