Ford Fiesta: Sill rust trapped behind side skirts and on door bottom edges (WP/WQ, worst on ST / XR4)
Sill rust trapped behind side skirts and on door bottom edges (WP/WQ, worst on ST / XR4) is a common body & rust fault on the Ford Fiesta on the 2004–2008 cars, and we rate it major. Putting it right costs $400 to $2,800 at New Zealand independent workshop rates. Below is what goes wrong, the symptoms to notice on a test drive, where to look, and what to ask the seller before you hand over any money. It is one of 16 documented faults on the Ford Fiesta.
- Vehicle
- Ford Fiesta
- Years
- 2004–2008
- System
- Body & Rust
What you are looking at
No photograph available
What goes wrong
On the WP/WQ Fiesta, rust commonly starts on the sills and along the bottom edges of the doors. On the ST (sold in Australia as the XR4) and other versions with bolt-on side skirts, the skirts are fastened onto the body and collect water and road dirt, holding it against the sill so the steel rots from behind the plastic where you cannot see it. Sills are structural and appear on the WoF/roadworthy check, so rust that has gone through means welding. Surface rust is cheap to treat; holes are not.
What you would notice
- Bubbling paint along the bottom of the doors or on the sill just ahead of the rear wheel
- Orange rust stains running out from under the side skirts
- Side skirt loose or sagging because its mounting points have rusted
- WoF or roadworthy failure for sill corrosion
How to check it
Where to look. Sills under each door (behind the side skirts where fitted) and the bottom edges of the doors
Crouch down with a phone torch and look along both sills from front wheel to rear wheel, especially the ends just in front of the rear wheels and behind the front wheels. Look for bubbling paint, rust stains or fresh underseal or filler that may be hiding repairs. On cars with side skirts, gently press along the skirt and look up behind its lower edge with the torch for rust and packed dirt. Open each door and check the bottom edge and drain holes for rust and flaking paint. Ask when the last WoF was and whether it listed any corrosion. If a workshop inspection is possible: have the car on a hoist and the side skirts unclipped so the sill steel behind them can be probed for soft spots.
What it costs to put right
$400 to $2,800 at New Zealand independent workshop rates. That is for this job on its own, not for the car.
Ask the seller
- “Has any rust or welding been done on the sills?”
- “Have the side skirts ever been removed to check behind them?”
- “Did the last WoF mention any corrosion?”
Now check the Ford Fiesta you are actually looking at
Everything above is true of the model, and it is free. What it does not tell you is whether THIS car has been looked after: its odometer history and whether the reading has ever gone backwards, whether there is still money owing on it, whether it has been reported stolen, how many owners it has had and what it is really worth today. That comes from the official records for that plate. Enter the plate for the free details, or get the full history and a market valuation from $13.49.
Where this comes from
- PistonHeads PH Fleet: Ford Fiesta ST Mk6 (rusty sills pretty common, side skirts trap water and muck against the sills)
- MicksGarage blog: Ford Fiesta 5th and 6th gen buying guide and common faults (rust on sills and door edges on the 2002-2008 car)
Ford Fiesta buyer questions
Is sill rust trapped behind side skirts and on door bottom edges (wp/wq, worst on st / xr4) serious on a Ford Fiesta?
We rate it major and common on the Ford Fiesta. On the WP/WQ Fiesta, rust commonly starts on the sills and along the bottom edges of the doors. On the ST (sold in Australia as the XR4) and other versions with bolt-on side skirts, the skirts are fastened onto the body and collect water and road dirt, holding it against the sill so the steel rots from behind the plastic where you cannot see it. Sills are structural and appear on the WoF/roadworthy check, so rust that has gone through means welding. Surface rust is cheap to treat; holes are not.
How much does it cost to fix on a Ford Fiesta?
$400 to $2,800 at New Zealand independent workshop rates. That figure is for this job on its own. A car showing the symptoms on this page is usually worth either walking away from or negotiating down by at least the repair figure.
Which Ford Fiesta years are affected?
Our research records this fault on the 2004–2008 Ford Fiesta. Build dates move around, especially on imported cars, so treat the range as the years to look hardest at rather than a guarantee either way. The official records tell you the exact build and first registration date for the car in front of you.
How do I check for it before I buy?
Crouch down with a phone torch and look along both sills from front wheel to rear wheel, especially the ends just in front of the rear wheels and behind the front wheels. Look for bubbling paint, rust stains or fresh underseal or filler that may be hiding repairs. On cars with side skirts, gently press along the skirt and look up behind its lower edge with the torch for rust and packed dirt. Open each door and check the bottom edge and drain holes for rust and flaking paint. Ask when the last WoF was and whether it listed any corrosion. If a workshop inspection is possible: have the car on a hoist and the side skirts unclipped so the sill steel behind them can be probed for soft spots. Look here: Sills under each door (behind the side skirts where fitted) and the bottom edges of the doors