Hey im new here, just wandering if anyone can help, I have a mk4 fiesta, 1.25 zetec s and its gota slight problem,...
When i am accelerating to change gear when i get to about 3500 revs it dies, doesnt accelerate anymore, but if i keep my foot down eventually it picks up, it takes a while though, theres definatly something wrong, i thought it could have been the fuel filter, but iv changed that, and no improvement, i have also changed the plugs and air filter.
If anyone could halp it would be muchly appreciated!
Thanks
Stephen

has it got a coil pack
clean the MAF
does it idle fine with not a SINGLE imperfection out the exhaust like a little break in the exhaust tone

Im not sure ill have to check, yep it idels fine, ill check tomorrow for nay imperfection too. Cheers what could ut indicate icf there were?

if it goes 'tut tut tut tut' out the exhaust then one or more of the 8 exhaust valves are either sitting bad or worn....

if it goes 'tut tut tut tut' out the air box in the engine bay then one or more of the 8 inlet valves are sitting bad or worn.....

go to a garage and get a compression check on each cylinder....one of them will be low on compression which tells you the valve is not sitting good or it has worn down and has a hole in it....

hope it helps you out as my car has the EXACT same problem and mine is getting fixed on sunday ....£160 parts £200 labourer

cam belt
every single gasket
head bolts
oil
antifreeze
new valves(probley have to get collets n coller as well for the correct valve fiiting)