Flashing yellow Engine management light on ford fiesta mk6 2002-2003

Flashing yellow Engine management light on ford fiesta mk6 2002-2003 Help?!

Added (1). ok so today my engine management light came on wilts i was driving slowly in town today
quite a hot day

the car feels as if it is struggling to accelerate after it warms up

i filled the water reservoir to the max yesterday

maybe i need to add coolant?

it gets rather hot under the bonnet even if i drive it for 5 minutes to work etc…

Added (2). it feels sluggish and struggles to get up speed

it sort of bumps… Jigs when i'm stationary… At lights etc…

The flashing light means that you are doing expensive damage to your vehicle if you drive it. You need to fix it now.