How urgent is it?
- Steady amber light. The car has logged a fault. If it's driving normally you can usually carry on, but get it checked within a few days.
- Flashing amber light. Usually a misfire. Ease off, avoid hard acceleration and get it looked at as soon as you can, because driving on can damage the catalytic converter.
- Red light. Stop when it's safe, switch off and call for help.
If the car has also lost power, it has probably put itself into "limp mode" to protect the engine. Drive gently and get it booked in.
Common causes
- A failing oxygen (lambda) sensor
- Worn spark plugs or a faulty ignition coil
- A dirty or faulty air flow sensor
- A blocked diesel particulate filter (DPF), common on diesels that only do short trips
- A sticking EGR valve
- A problem with the catalytic converter
- A loose or worn fuel filler cap
Will it go away on its own?
Sometimes, if the cause was a one-off. More often the light comes back. Clearing the code with a cheap reader turns the light off, but it doesn't fix the fault that caused it.
Will it fail the MOT?
On most modern cars, yes. An engine management light that stays on is an MOT failure, so it's worth sorting before your test.
What a diagnostic check involves
A fault code tells us where to start looking, not which part to replace. We read the codes, then test the parts and wiring involved, so you only pay for the repair you actually need. We call you with what we've found and a price before doing any work.
Want us to take a look?
Book online in about a minute, or call 01323 315609.