Ford Territory Engine Problems

This is not uncommon. Ford chose not to service the ignition switch separately, so when it fails the only option left to owners is to replace the whole assembly and considerable cost as you found out. I can only assume they did to save money on the stock of spare parts they carried.

The first thing to do is to check the battery to make sure it's ok. If it is the original battery, it's now five years old and could well be in need of replacement. If the battery checks out ok I'd be checking the engine sensors, like the crank angle sensor, and their connections.

It’s not common, so I would suggest you could have a problem with the LPG system. The LPG mixture could be off causing the converter to run hot or foul, or it could be backfiring and destroying the converter’s innards.

From what you describe you should be able to hear it if you lift the bonnet and from that you should be able to isolate it to a particular part of the car. If you can do that you can fix it. Take it to a mechanic.

Without being able to hear the noise you complain of it's hard to say what it might be, but the possibilities are valve lifters or piston slap. Because your dealer and Ford have been unhelpful, the dealer seems to have wiped their hands of the problem, seek independent advice from a reputable mechanic and take that advice back to the dealer in the hope they will address your concern.

It's likely that the converter has collapsed inside and is partially blocking the exhaust. It's not too common, but it does happen, and not just with Fords. The answer is to fit a new converter.

HAVE you checked the engine to see if it is coming from there? It sounds awfully like the engine itself, perhaps a faulty valve lifter, because it goes away when the engine warms up. An engine noise might sound like it's coming from under the dash.

It could be that the starter gear and the ring gear it engages are not mating properly; it could be that either is damaged. It could be that the solenoid on the starter is not throwing the pinion gear with sufficient power to cleanly engage the ring gear. Have the starter removed and checked, at the same time the mechanic should be able to check the ring gear for damage, and check the solenoid on the starter.

Yes, you can. You should see improved performance and better fuel economy, hopefully enough to offset the higher price of the petrol.

It sounds like it might be a sensor and checking the crank angle sensor was sensible. I would also check the knock sensor, which is there to detect detonation and retard the ignition enough to prevent it from happening.