Ford nearly built a Mustangengined Mk2 Capri…
You’ve probably heard loads about the one-litre EcoBoost. Its cast-iron cylinder block will fit onto a sheet of A4 paper, and the entire unit weighs just 97kg. It’s been tuned to produce 202bhp in a single-seater Formula Ford racer wearing an ST180 turbo, while negative press reports have renamed it EcoBoom and EcoBust after a series of catastrophic failures. Bad news? Well no, not really. Millions of EcoBoost units have been produced, and it’s still only a small percentage that have gone bang. The overwhelming majority were found in Ford Focuses, which in most cases required complete new engines from as early as 15,000 miles. Problems seem to centre around the cooling system – including head gasket failure – so it’s wise to check the car you’re buying has no obvious coolant leaks.
Steer clear of any dashboard warning lights, and an engine running rough or in limp mode is to be avoided – as are nasty noises, although it’s normal for a 1.0 to sound a bit rattly. Ensure the oil level is correct, and you’ll need to see a full service history, with oil changes every 12,000 miles. Ford’s warranty demands unusual 5W20 oil, although AET Motorsport recommends 5W40 Millers for modified cars - but warm up the engine before driving hard. Incidentally, the cam belt runs in the oil, and needs replacing at 150,000 miles or ten years.
There’s no apparent pattern to failures – or specific warning signs – but neglect could be a factor. Top tuners have taken EcoBoost one-litres to high power outputs without problems – Collins Performance has a modified demonstrator with 40,000 miles, while AET’s own Fiesta has covered 50,000 miles with stage two and remains problem-free.
AET recommends 98 RON fuel, especially on a tuned car – expect to see negative effects with poor petrol and/or bad remapping. Reputable tuners don’t push a 1.0 beyond 175-to-180bhp and 190lb.ft torque – after which there’s a real chance of snapping the crankshaft, and a forged bottom end is required.
All engines – 100, 125 and 140PS – are mechanically identical, although the 140 has an uprated head gasket. We’d advise buying a 125 or 140 because they tend to be sportier models.
If you fancy a modified Fiesta, be sure it’s been done properly, with safety features left in place. The stock intercooler is on its limits in a 140, so be suspicious if the seller’s claiming big power without one.
The turbo runs exceptionally hot, and Collins offers hybrid turbos through Turbo Technics, where internal cracks have been discovered at strip-down; expect to find wear on a heavily-used example. Pop off the induction pipe, remove the heat shield, and make sure the compressor wheel isn’t damaged; give it a wiggle to check for play.
Finally, if you’re at all afraid of the EcoBoost, check out what an extended warranty can offer.
The IB5 gearbox is the Fiesta’s weak link and doesn’t like loads of torque