What Is Limp Mode? Causes, Symptoms & How to Fix It
FixMyCar explains what limp mode is and guides you on the safest next steps.
Book a car repair nowEllie Dyer-Brown
Friday February 02 2024
6 min read
Modern cars contain many safety features that run in the background. Most of the time, you hardly notice them, and you don’t necessarily need to know how they work. But when it comes to limp mode, you’ll notice something’s wrong straight away. Understanding why it happens - and what to do next - can help you avoid further damage.
In a nutshell: Limp mode is a safety feature that cuts your car’s power when the computer detects a fault, usually to protect the engine or gearbox. The car will feel sluggish and may be stuck in one gear but should still move so you can reach a safe place or garage. It’s important to get a diagnostic check to find and fix the cause rather than trying to ignore or bypass limp mode.
What is limp mode?
Limp mode - sometimes called “limp home mode” - is a safety feature in modern cars. When the car’s computer (ECU) detects a fault that could damage the engine or gearbox, it reduces power and limits performance so you can drive slowly to a safe place or a garage.
It’s the car’s way of protecting expensive components until the problem is diagnosed and repaired.
Is it safe to drive in limp mode?
Limp mode is designed to let you drive a short distance to safety or to a garage. You should avoid motorways, towing, heavy acceleration but switch your engine off and call for help if the engine temperature rises or you lose brakes/steering.
Stop driving immediately if you notice:
Burning smells or smoke
Overheating
Loud knocking noises
Severe loss of control
When in doubt, it’s safer to pull over and call for help.
Why do cars go into limp mode?
Your car constantly monitors sensors in the engine, gearbox and emissions system. If something looks unsafe or out of range, the ECU triggers limp mode to prevent damage. Some of the most common causes are covered below.
| Cause | Avg repair cost |
|---|---|
| MAP sensor | £50–£150 |
| Turbo boost pressure fault | £100–£500 |
| Transmission fault | £200–£800 |
| Overheating | Varies |
Engine or turbo problems
Blocked air intake, turbo boost issues, misfires or fuel delivery problems can trigger limp mode to protect the engine.
Gearbox or transmission faults
Overheating, hydraulic problems or internal wear may cause the system to limit power.
Sensor or wiring faults
Modern engines rely on sensors such as the MAF, MAP, throttle position, crankshaft or boost-pressure sensors. If one sends incorrect readings or wiring becomes damaged, the ECU may enter limp mode as a precaution.
Low or incorrect fluids
Low engine oil, coolant or transmission fluid can cause overheating or lubrication problems, which will trigger limp mode.
Learn how to check your car's fluid levels.
DPF or emissions system issues
A blocked diesel particulate filter (DPF) or EGR fault can also cause reduced power on diesel cars.
⚠️ The underlying cause isn’t always obvious. In most cases, a mechanic will need to read the fault codes to confirm what’s wrong.
What should you do if your car goes into limp mode?
Stay calm and drive gently, avoiding hard acceleration.
Move somewhere safe such as a lay-by, car park or service area.
Switch the engine off for 30-60 seconds and restart it.
If limp mode clears but comes back again, there is still a fault that needs attention.
Check basic essentials only if you’re comfortable doing so (oil level, coolant level, obvious leaks).
Book a diagnostic inspection as soon as possible so a mechanic can identify the cause.
Driving in limp mode for a short distance is usually fine, but continuing to drive normally or ignoring the warning can lead to expensive engine or gearbox damage.
Common symptoms of limp mode
When your car goes into limp mode, you may notice:
Engine management light (pictured below)
Revs limited to around 2,000-3,000 RPM
Locked to a low gear (in automatic cars)
Auxiliary functions may stop working (e.g. heating and aircon
Can you fix or reset limp mode yourself?
Sometimes limp mode is caused by a temporary issue, such as a brief sensor glitch, and restarting the car may clear it. However:
If the underlying problem remains, limp mode will return
Clearing the warning without fixing the fault won’t solve the issue
Attempting to bypass or disable limp mode can cause serious damage
The safest and most cost-effective solution is to have the car professionally diagnosed so the real cause can be repaired.
How much does it cost to fix limp mode?
The cost depends entirely on the fault that caused it. A simple sensor or wiring issue may be relatively inexpensive, whereas transmission or turbo faults can be much more costly.
| Cause | Avg. repair cost |
|---|---|
| Gearbox | £382.77 |
| Transmission | £288.86 |
| Turbo fault | £769.51 |
| Sensor | £137.80 |
Most repairs begin with a diagnostic check (average price: £61.85), which helps pinpoint the problem before any parts are replaced. This prevents guesswork and keeps costs under control.
Frequently asked questions
You may see the glow plug warning light while your car is in limp mode. However, this does not necessarily mean the glow plugs are causing your car’s lack of power. This guide discusses what happens when your glow plugs fail.
Particularly in Skoda, Vauxhall and Peugeot models, problems with the diesel particulate filter (DPF) can trigger the glow plug warning light. In this situation, the DPF, rather than the glow plugs, is causing limp mode.
Because the computer detected an issue, commonly related to sensors, the engine, turbo, transmission, low fluids or the emissions system.
Yes, low oil can affect lubrication and temperature, which may trigger limp mode to protect the engine.
It may temporarily reset after restarting the engine, but it will return if the fault is still present.
The only reliable way is to fix the underlying problem. A diagnostic test is usually the first step.
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Ellie is FixMyCar's Content Manager. She has over three years of experience writing about cars and regularly collaborates with automotive experts to provide trustworthy advice for drivers that is easy understand. Her work has been featured in Yahoo! Finance, iNews, The Daily Express and The Sun. She has a BA in English literature and an MA in creative writing from Durham University. Outside of work, Ellie follows F1 and eagerly awaits Ferrari's next era of dominance in the sport. She drives a Suzuki Swift.