Why does my sportage spontaneously shift into neutral when accelerating at 70mph?

Question edited for clarity and spelling.
Question moved to model category from 'Misc'.

Check for Diagnostic Trouble Codes. check clutch operation if manual. Check transmission fluid if automatic.

'Passing gear' is a term that means the transmission is down-shifted to a lower gear (e.g., from 5th gear to 4th gear) for improved acceleration to pass another vehicle. There is no physical component called a passing gear in the transmission.
To engage the 'passing gear' with an automatic transmission should require nothing more than pressing the accelerator pedal down firmly. The transmission should downshift automatically to the next lower gear (sometimes it will downshift two gear ratios, depending on your speed and how far you depress the accelerator pedal).

Have you had fuel pressure tested, as well as exhaust for possible plugged catalytic converter?

Look for a blown fuse in the fuse box.

Hi - Here is instruction how to do.

From N to 4H

Stop the vehicle completely, place the

transmission in "N" (Neutral) and depress

the brake pedal and the clutch pedal fully

(if equipped), then push in and turn the

switch to shift into "4H".

From 4H to 4H LOCK

You can operate the transfer switch either

when the vehicle is stopped or while the

vehicle is moving.

Position the front wheels straight ahead

and turn the switch to shift into "4H LOCK".

If the vehicle is moving, we recommend

that the speed be less than 100 km/h (60

mph) during this operation.

NOTE:

• When shifting between the transfer

switch position and the transfer gear

position is unmatched, all 4WD indicators

will blink and the buzzer will sound.

• If it is difficult to shift between "4H" and

"4H LOCK" while the vehicle is moving,

try accelerating and decelerating your

vehicle several times after turning the

transfer switch. Be sure to wait until traffic

conditions allow you to accelerate and

decelerate safety before using this procedure.

From 4H LOCK to 4L LOCK

Stop the vehicle completely, place the

transmission in "N" (Neutral) and depress

the brake pedal and the clutch pedal fully

(if equipped), then push in and turn the

switch to shift into "4L LOCK".

From 4L LOCK to 4H LOCK

Stop the vehicle completely, place the

transmission in "N" (Neutral) and depress

the brake pedal and the clutch pedal fully

(if equipped), then push in and turn the

switch to shift into "4H LOCK".

From 4H LOCK to 4H

You can operate the transfer switch either

when the vehicle is stopped or while the

vehicle is moving.

Position the front wheels straight ahead

and turn the switch to shift into "4H". If the

vehicle is moving, we recommend that the

speed be less than 100 km/h (60 mph) during

this operation.

NOTE:

• When shifting between the transfer

switch position and the transfer gear

position is unmatched, all 4WD indicators

will blink and the buzzer will sound.

• If it is difficult to shift between "4H" and

"4H LOCK" while the vehicle is moving,

try accelerating and decelerating your

vehicle several times after turning the

transfer switch. Be sure to wait until traffic

conditions allow you to accelerate and

decelerate safety before using this procedure.

From 4H to N

64J209

Stop the vehicle completely, place the

transmission in "N" (Neutral) and depress

the brake pedal and the clutch pedal fully

(if equipped), then push in and turn the

switch to the mark (1) at the left of the "N"
position, and hold the switch in this posi-

tion for 5 seconds until the "N" indicator

blinks, then turn the switch to the "N" position.

When you turn the transfer switch to the

"N" position, "N" indicator will come on with

the buzzer sound.

CAUTION

• Be sure to stop the vehicle completely

before operating the transfer

switch to shift between "N" and

"4H", or between "4H LOCK" and

"4L LOCK".

• Do not shift between "4H" and "4H

LOCK" unless the front wheels are

in the straight-ahead position and

we recommend that the vehicle

speed be less than 100 km/h (60

mph).

Do not operate the transfer switch

while tires are racing.

• Do not operate your vehicle in "4H

LOCK" or "4L LOCK" on dry, hard

surfaces.

(Continued)

CAUTION

(Continued)

• Do not operate the vehicle while a

4WD mode indicator is blinking

except when shifting between "4H"

and "4L LOCK".

If you operate the vehicle while a

4WD mode indicator is blinking, a

buzzer will sound and the transfer

will shift to "N" (Neutral) to prevent

transfer case damage.

In this case, use the following procedure.

1) Depress the clutch pedal fully (if

equipped) or shift the automatic

transmission gearshift lever to the

"N" position.

2) Turn the transfer switch to the

position previously selected.
3) Operate the transfer switch again.

First-NEVER add anything to an automatic trans.
Your vehicle should use Mercon V --PERIOD
Change it at least three times, to get the Lucas out.

Have the TPS Sensor checked out.
You most likely have a Tran Pack Solenoid going bad.
It is bolted to the valve body. You can do it yourself

If it is automatic transmission you must stop vehicle put it in neutral or "n" then put shifter that is indicates 2h 4h and 4L pull down to 4h if you are driving on highway or pull down then over and up to 4L if you are not going to be driving faster than 30mph.
If manual put in neutral also and do the same process as automatic there will be a light on dash board indicating that it is in 4wd also put transmission back to drive on automatic or shift to first gear on manual

How many gears does your car have? One of my cars has to do a little over 3000rpm to maintain 70-75 in 5th gear. My other car has to do about 3000rpm to maintain 65-70 in 5th gear.

It all depends on the number of gears your car has and the gearing ratio. The second car I have is geared more optimally for city driving and gets better fuel economy going slower than fast highway speeds.

Having driven several rental cars too I would say anywhere between 2500 to 3000 is reasonable for the average car. If you are driving a vehicle like say a porsche, bmw or audi they may have more gears and may be at a lower rpm at 70mph than your car.

Sounds like a transmission problem. If the vehicle is having the issue at a high gear then I suggest you take it in and get the tranmission flushed this may resolve the issue and only cost about $60.

Do you know if you have a 4L60E or a 4L80E?