Niggling fiesta issues

[millsydt]

Im a bit baffled now iv had sum niggling issues with my fiesta if i accelerate briskly around 40-50 mph and sometimes 60-70 i feel the engine holding back its got a brand new set of spark plugs by the looks of things i new coilpack the air filters clean brand new fuel filter too i cleaned the inlet too seems to run a bit better on Shell fuel iv noticed its a 96 fiesta 1.25 lx

Can anyone help

[KatePocket]

Im a bit baffled now iv had sum niggling issues with my fiesta if i accelerate briskly around 40-50 mph and sometimes 60-70 i feel the engine holding back its got a brand new set of spark plugs by the looks of things i new coilpack the air filters clean brand new fuel filter too i cleaned the inlet too seems to run a bit better on shell fuel iv noticed its a 96 fiesta 1.25 lx

Can anyone help

My corsa used to do this, it was an S reg, so 98/99, but it turned out to be the air filter. Does it happen when you're going up hills too? I used to find that i hadf to change down a gear or 2 to stop it, the engine warning light used to come on and then go off again also.

We had to take it to the vauxhall garage to get it diagnosed though, i imagine that somewhere with a diagnostics computer will be able to tell you what's wrong, but it could end up being quite pricey.