@@dusan211 there can be a lot of reasons, like a misfire, air to fuel ratio failure or a bad sensor for example, but the ignition system can in most cases be the cause, so you may have bad spark plugs, bad ignition cables or bad ignition coils.
It has to be removed before starting the engine, otherwise it may sit in the opening of the valve and keep it open and let the piston hit the valve, or it may get inside the cylinder and damage the engine more.
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What causing check emission error?
@@dusan211 there can be a lot of reasons, like a misfire, air to fuel ratio failure or a bad sensor for example, but the ignition system can in most cases be the cause, so you may have bad spark plugs, bad ignition cables or bad ignition coils.
What if is a metal bolt that has fallen inside What will happen
It has to be removed before starting the engine, otherwise it may sit in the opening of the valve and keep it open and let the piston hit the valve, or it may get inside the cylinder and damage the engine more.