Pls Help?

[Jamiegreen02]

Hello all,

I bought a fiesta last November. It was a 1.25 but has been converted to the 2.0 st. Hes actually not done a bad job. Anyway ever since I have owned it, it drives nice when its cold. Soon as the engine gets up to temp the car starts holding back. When I go to accelerate it like delays then starts going and also has very little power when this happens to. Have now changed plugs, leads and coil pack. Anyone know what my issue could be. Thank you

 

[D1JL]

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Dave

 

[XR650R]

Welcome!
Can you check it for codes?

 

[M-Sport fan]

Is this a Mk7, or a Mk6 Fiesta??

 

[Jamiegreen02]

Welcome!
Can you check it for codes?

Hello I have checked it for codes. All im getting is a oxygen sensor fault. Guessing its due to decat.
Its a mk6 fiesta st

 

[XR650R]

Hello I have checked it for codes. All im getting is a oxygen sensor fault. Guessing its due to decat.
Its a mk6 fiesta st

Not sure if that's what's causing it to go limp, but I'd start there.

 

[Dpro]

Welcome.