Ford Fiesta 2001 56500 miles slowing on hills and unusual behaviour?

[mattsmako]

Hard to tell for sure but take a look at the air filter or the fuel filter. Sounds like its not getting enough of one or the other. I assume there are no unusual noises? Could also be bad gas, run the tank as low as you can within reason, and try a different gas station. Sometimes you get gas from a tank that's low and can pick up water or trash. These are the easiest least expensive items to look at. Hope this helps.

[codenamematt2007]

Had it for 6 months now, was running perfect until recently where it slows to almost crawl up hills, having to shift from 25mph gear two to three which used to be from 20mph, and if I stretch the gear my pushing the accelerator further it sort of shudders.

I'm not sure if it has anything to do with me damaging an alloy and running on a spare tyre for a week, which is now replaced with new tyre and alloy, but as you can tell I hit the curb hard for the alloy to be damaged, but this was about 2 months ago and was replaced a while back, but that is the latest milestone I can think that it began.

Any mechanical help or causes I will be thankful for. P.S Oil is fine
Also I couldn't reach over 55 on the motorway on the spare, but I don't think I could even reach that now with the new alloy and tyre.

[mattsmako]

Hard to tell for sure but take a look at the air filter or the fuel filter. Sounds like its not getting enough of one or the other. I assume there are no unusual noises? Could also be bad gas, run the tank as low as you can within reason, and try a different gas station. Sometimes you get gas from a tank that's low and can pick up water or trash. These are the easiest least expensive items to look at. Hope this helps.