Automatic transmission on limp - 2001 Daewoo Tacuma 2.0

o/d off light is flashing? Hook up a scan tool an check for DTC'S - diagnostic trouble codes, transmission problem.

Which transmission does your vehicle have

SECTION 307-01A: Automatic Transmission - 4R70W
SECTION 307-01B: Automatic Transmission - 5R55E


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getting rid of the cat converter is the worst idea that has been put into your head
It is there for a purpose , improves economy, doesn't restrict performance and if removed places you in a position for an unauthorized modification that can cost a lost of cash
and yes it can put the engine in limp mode as it affects the engine sensors and that affects the air/fuel settings
And yes problem in transmissions will put the engine in limp mode as the program is to protect a failing transmission as well as an engine

probably not if it is limp mode
the ECM puts the car in limp mode to prevent serious problems in the engine or transmission
could be no coolant, sump oil , transmission oil etc
run the fault codes and find the reason for the mode

There are major faults that need to be addressed. The car is in limp mode because the computer is saving the engine or transmission from damage if the car is driven. IF you ignore the problem and do nothing to have the vehicle problems diagnosed and fixed it will stop running altogether.

You get it out of limp mode by fixing the problems with the vehicle - not ignoring them.

You may not be able to come out of limp mode until the problem the computer is seeing is repaired. The computer determines if something is affecting proper engine/transmission operation and for safety implements LIMP mode to protect other operating systems from possible damage. Do a diagnostic scan and repair the problem

Sounds like your tansmission is in limp mode to protect itself.

you'll probably need to identify and correct the speed sensor problem (at the wheels or at the transmission sensor) before you'll be able to get it out of limp mode.

"Limp Mode" is determined by the Powertrain Control Module (PCM). It could be going into limp mode as a result of a transmission malfunction or it may be going into limp mode as the result of an engine control problem. The only way to find out is to scan your onboard computer system and retrieve any engine or transmission fault codes and diagnose and repair accordingly.

Please note that engine control problems can CAUSE transmission control problems. If there are any engine control faults, these MUST be diagnosed and repaired FIRST.

Please also review these articles:

What Else Could Be Wrong?

What To Expect From An Online Car Expert

Most transmissions have a limp mode, or limp-home mode.
If the driveline computer thinks there is something wrong, it can lock the transmission into one gear, such as 2nd gear. Usually reverse will also be available. The Impala automatic has 4 speeds. 2nd speed or gear will get you home, but the engine rpms can get a little high. I wouldn't get on the expressway will in limp mode.
Before taking to the shop, you might want to try and reset limp mode by turning the car off for a couple minutes, or you may have to disconnect and reconnect the battery.

The blinking arrow is an indicator that the automatic transmission is in the limp mode. Sometimes this problem will go away. Other times you must take it in and have the error code on the transmission read. This will explain what is causing the transmission to go into the limp mode. The limp mode is the same as the WINTER mode where it starts in 3rd gear.
The dash board gauges are controlled by a dimmer switch that is above the rear fog light switch which is above the headlight switch. If this dimmer switch doesn't work, then have it replaced.

the vehicle may have a electrical problem and or mechanical problem in the trans....id try replaceing the solenoids and then the entire transmision and torque converter.