I'm guessing this is the 2.0 IDE
. My previous car (also an 02 2.0) had pretty much the same problem, though it used to throw up "Fuel injection system faulty" followed by "ESP faulty" and occasionally "Anti-pollution system faulty."
Most times, I could recover from 'limp home' mode by stopping and re-starting the engine. On the few occasions where that didn't work, I took the car to the dealer. Sometimes it stored a fault code, sometimes it didn't. Whenever it did, it was invariably something to do with no.2 injector.
The dealer eventually replaced no.2 injector (and left me with fuel spraying all over the engine compartment, but that's another story.) I changed cars a few weeks later, so I can't be certain that the fault was cured, but it didn't come back during the remaining time that I had the car.
Due to the design of the IDE
, the injectors are a nightmare to get at. It looked to me like the intake manifold had to come off at the very least, though that may just have been the tip of the iceberg.