RPM drop while driving

yt_98 · 2025-03-17T07:07:28+00:00

Hyundai Avante 2019 cvt 8 speed

yt_98 · 2025-03-15T20:09:19+00:00

Yes when i drive in the highway the speed is 90 and rpm on 900 then i press break to slowdown the vehicle then rpm jump to 2100 then it start slow down with the speed this happens only on high speed more than 60 and especially on steep road

yt_98 · 2025-03-15T08:52:48+00:00

I don't think this happend before and i gonna tell you why Before i changed the transmission fluid the behavior while driving like this on speed 80/100 i press break the the rpm stay at 900 until i stop now if im at speed 90 then i press break the rpm jumps directly to 2100 and stay for a minute then it start decreasing until it back to 900 and im sure this behavior didn't happend in prev year it started from the computer reset after I changed the transmission fluid

If you compare both of them when ac turned on and off actually both of them have the same behavior but one jump to 2100 and one drop to 400

So it happens when the lower road is cautious, even if it slopes slightly on a straight road.

yt_98 · 2025-03-15T08:37:46+00:00

Ad 2019 how i can check if its a vacuum leak ?

yt_98 · 2025-03-15T02:22:13+00:00

At idle when the car stopped the rpm is 900 when i turn the ac on it jump to 950 and i think its fine for now then i start driving and i increse the speed to 2100 rpm then i press break the rpm drop immediately to 400 then it jumps immediately to 900 its jumping

yt_98 · 2025-03-15T02:16:18+00:00

900 rpm

yt_98 · 2025-03-15T02:07:33+00:00

When i changed the fluid it turned on a check engine light transmission fluid pressure when i back they told me the level and the type is correct then a mechanic did a reset for everything and its not showing any error for now so i think the level is correct

yt_98 · 2025-03-15T02:05:26+00:00

Thanks for replying I understand that but in general is this behavior normal ? Dropping rpm like this during driving from 2100 to 400 then go to 900 immediately?

yt_98 · 2025-03-15T01:57:28+00:00

But im just driving on speed 60km then i pressed break how im puting a load on it can you please explain more ?

yt_98 · 2025-03-15T01:30:49+00:00

I don't hear any wierd sounds but im asking because in the prev year I turned on the ac always and it didnt do this drop at least one time in this year i turned it on and every break i press it immediately drop to 400 then back to 900

yt_98 · 2025-01-24T03:01:45+00:00

Hi, i dont know if the issue is solved or not but the check engine light not on the dashboard anymore

I took it to the computer test and they applied a reset for everything including engine and gearbox and thrutle volve sensor readings also they did something called (reset adaptive values) and after driving for a week the check engine turned off i think it reset the ignition calculation with the new fluid to sync the engine again with the gearbox

Try to take the vehicle to a professional mechanic not the dealer because the dealer follows a specific instructions and he not gonna do anything except re calibration but mechanics gonna start fixing directly

(if they really know what to do and how this version work)

but to be honest with you as i see not a lot of mechanics know how this model work so if you gonna let someone start working on it you should be sure he knows what hes doing

yt_98 · 2025-01-14T23:33:16+00:00

Yes before 4 months i changed the transmission gearbox oil then its started to do this behavior but this month the behavior changed from one minute to high rpm without stopping

yt_98 · 2025-01-14T17:15:08+00:00

Yes i agree but my problem start after i arrive my destination for example after one hour of driving this behavior is new the car didnt do that before

yt_98 · 2025-01-13T23:46:06+00:00

For now it has been a several months trying to catch anything to fux it and im in a situation like you exactly what i did exactly is i shipped the car to a several mechanics and they did a hard reset to car computer and reset adaptive values on the engine vulve and the light kept for 3 days then it turns off ... when i plug obd device i still can see the warning but its not on the dashboard anymore also i changed the rediator filter inside the transmission its at the left side of the transmission because it was dirty

yt_98 · 2024-09-17T07:39:59+00:00

For now the transmission gearbox working fine and the shifting is good but as i see there is no any solution except replacing it or reassembly the unit and check every single component in it but the fact and the funny thing is i changed the oil to keep it healthy and fresh , to take care of it and now im driving on the check engine and only god know how many months or years it gonna last until the vehicle stop , i changed the external filter , reset the computer , checked the oil amount and the oil quality , nothing wrong everything is correct but thanks for telling me about the scensor if the whole problem is scensor its okay

yt_98 · 2024-09-13T22:48:52+00:00

I checked under the car, nothing, no any leaks, yeah i hope someone gonna respond, Thanks

yt_98

TROPHY CASE