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Q: Amber engine light came on. Mechanic said the fault was a knock sensor.

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I have a Mazda demio 2004 and it's done hardly any mileage. About 44,000km.

I drive a lot of kms a week to and from work and 2 days ago the amber engine light came on.

I took it into the garage and they have come back with the fault being a knock sensor. As I drove away the lights came straight back on. I rung them and they said that it could be back on at anytime.

Basically the conclusion they have is that it requires removal of inlet manifold to access this. And it comes at a hefty price which I cannot afford for another few weeks.

My question is am I safe to keep driving my car until i can afford to get this done? I'm worried that if I leave it to long then I will break down. How serious is this?

My car has 30000 miles.
My car has an automatic transmission.

A: If your engine has any kind of noise in it ...

If your engine has any kind of noise in it that can cause an engine knock then it would also set the code for the knock sensor. The knock senor is used by the computer to adjust ignition timing for maximum engine performance and fuel mileage. If you do have a defective sensor you may notice besides the check engine light being on the engine may have power and performance issues and lower fuel mileage. Have the sensor replaced when you can if that is the actual problem. Have a mechanic like one from YourMechanic come and confirm diagnosis is the sensor and not an internal engine noise causing the fault.

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