Q: Car suddenly went into limp mode

asked by on

After some off-roading last friday, the car suddenly went into in limp mode, doesn't go faster than 40Km/h with the pedal to the metal and makes awful sounds. I don't know if it's related but have recently changed brake pads and brake sensor switch, transmission oil

My car has 157000 miles.
My car has an automatic transmission.

Hello and thank you for contacting Your Mechanic. Your Hummer could have the brake system engaged for the traction control. Disable the traction control and see if the engine will increase in speed.

Another thing to check is the parking brake cable. See if the cable is snagged on anything causing the vehicle to have a dragging resistance in the brakes. If the brakes are free and working correctly and if the engine continues to be in limp mode, then there could be an issue with the transmission.

Check all of the harness connections to all of the sensors on the transmission and transfer case. If all of the connections are tight, then I recommend having a professional, such as one from YourMechanic, drive your Hummer and determine why your car isn’t getting enough power and is making unusual noises.

Was this answer helpful?
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details
  1. Home
  2. Questions
  3. Car suddenly went into limp mode

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Q: Q: Power window not working

The most likely causes of your power window not working are the motor, or the regulator. If you hear the motor noise, but the window does not move, then the regulator is broken. If you do not hear the motor,...

Q: Rough acceleration and sputtering

The regulator is mounted to the fuel filter housing where the fuel line goes in. You may have a bad injector or two that is causing the problem you are having. The injectors on these engines had issues that are...

Q: Q: I replaced the Vent Valve Solenoid and Purge Valve and the check engine light came back on again for P0449 like before the repair.

It is very possible that you can have a clog in your EVAP system somewhere preventing flow. I would recommend having the lines cleared out with some compressed air if possible by a qualified professional.

Related articles

How Do Power Car Windows Increase Passenger Safety?
Power windows are responsible for approximately 2,000 emergency room visits every year. When a power window closes, it exerts enough force to bruise or break bones, crush fingers, or restrict an airway. Though...
How Long Does a Distributor O Ring Last?
The distributor is part of the ignition system in your vehicle and its purpose is to route high voltage from the ignition coil to the spark plug. The spark plug then...
P2103 OBD-II Trouble Code: Throttle Actuator Control Motor Circuit High
P2103 means there is a fault with the throttle actuator control motor circuit, likely due to a defective electrical component or part.