Have a 2009 1.25 Fiesta which will start perfectly when cold.  However if I drive the car for a period of time, switch it off and then try and start it again (ie go to a petrol station and fill up), it won't start unless I pump the accelerator pedal at the same time as turning the ignition.

Complete novice but have done the following checks after checking forums, YouTube etc:

• Checked Air filter
• Cleaned the throttle body
• Replaced the crankshaft position sensor

Next check is the camshaft position sensor but struggled to remove it first time as seemed to be stuck.

 

Any thoughts?

I had the same issue when I had my 2009 fiesta. Change the starter motor. When I did that on mine I didn't get a reoccurrence of the issue. I saw somewhere (may have been on my post on here about this) that the factory starters last about 10 years or 100,000 miles before needing to be changed.

Once you start using the accelerator pedal to start the car, it messes up the PCM's (ECU's) learnt values.
Before you dive any deeper into part replacements try the following.

Disconnect the vehicle battery for a couple of hours.
Reconnect battery.
Ignition switch to position II, do not turn to start. Wait 1 minute then turn off. (Throttle body calibrates)
Start car without touching accelerator and then see if it fixes your warm start issue.
You should never need to touch the accelerator pedal when starting.
 

@Dan62 - I followed your suggested approach but results afterwards were still the same.  What i did notice was that i did not need to pump the accelerator but it took until the 3rd attempt before the engine started.  Perhaps it is the starter motor as @King683 suggests?

We are on holiday tomorrow so will need to look at replacing the starter motor when I return.

Just incase you need it, the photo attached was of my oem unit that I took out of my old car when I changed mine. I found that some places namely on ebay wanted some of these numbers to verify that the part fit or was correct for the car. Or you could go straight to your preferred car parts store and order one. 

Try better quality fuel, check HT leads, they may be breaking down when hot, ensure correct spark plugs fitted and correct gap, put some additive in to help with "coking", ensure oil is fresh and correct grade, ensure air filter is clean.

Could also be coil pack starting to go down

For me also look like starter issue.. With different model car, I experience same case due worn bearing issues. 
Sometimes if you pour cold water on top of it and it start from the first attempt.
Also, if you use ampere clamp multimeter around the battery lead, you can see right away the difference in current drain when cold and warm.
In the old cars similar issue was caused by small valve clearance and after proper adjustment was cured. If here the gap is controlled by hydraulic lifters forget about it..

Before me, was mentioned the coil pack. Could you check when it is warm and spray with soup water does it stall..
Sometimes crack in the coil get wider when warm and if engine run you can not exactly feel it.
Yet, if the air is with lot of moisture, the next start is hard similar to bad cranck sensor..

Just thoughts.. 

In the pre-injector days, this would indicate fuel flooding, and you'd look for spark plugs possibly wet and smelling strongly of fuel.  With fuel injectors, the only thing that could cause this is if some of them leak when not activated.

Of course it could be many other things, as mentioned by others; but I think this one is worth adding to the list.

You'd get a check engine light if there was a problem with the CPS.

On 4/29/2025 at 6:04 AM, King683 said:

I had the same issue when I had my 2009 fiesta. Change the starter motor. When I did that on mine I didn't get a reoccurrence of the issue. I saw somewhere (may have been on my post on here about this) that the factory starters last about 10 years or 100,000 miles before needing to be changed.

Bit late to respond but as per King683, once the starter motor was replaced the problem disappeared.