I have a 1.2l 2003 Fabia, with 151k on it (I've owned it since 6k). It's been regularly serviced and has had a new cat at approx 75k, new power steering management chip and engine temp sensor about 7 months ago.

3 weeks ago after a regular service (full service spark plugs were done as well) I started having problems - the engine was "spluttering" during gear changes or acceleration. Brought it back to the garage and they eventually diagnosed a slightly snipped lead to the coil pack. While it was in for this problem they also changed the O2 sensor as it was showing as a fault code in the advanced menu (their words).

Last week I started having a new, unrelated? problem - sudden loss of power at speeds in and around 125kph and dropping revs. When I made it off the motorway there was a nasty burning smell but that had long dissipated by the time the AA arrived. They couldn't find a problem (he checked the oil, clutch, had a quick peek at the engine, took it for a test drive and tried to suggest it was my driving as I'm female ) and told me it was fine. Heading home from work that evening it happened again and I insisted they tow the car to the garage. The engine management light did not come on (I'm familiar with that delightful light thanks to the cat) at any point and, other than the loss of power at speed in excess of 100kph for more than 10 minutes or so, it's driving fine.

The only fault code pointed towards a crankshaft sensor so that was replaced on Friday and they sent the car home with the understanding that it may/may not be fixed but they couldn't test it at speed. Heading into work this morning it happened again - so I pulled over, waited 10 minutes and continued on my way as my garage is closed today for a family funeral and the AA weren't able to find the problem last time.

I'll be bringing the car back to the garage tomorrow (assuming I make it home!) and was just wondering if anyone had suggestions as to what might be wrong ? The impression I got from the mechanics on Friday was it might be an intermittent fault and thus hard to diagnose and fix.

The rest of the car is in fairly good nick and I do have an engine fund as I'm aware that 150k+ is high mileage for a 2003 3 cylinder Fabia.

A burning smell after a sustained spell at 120kph makes me wonder if the clutch is just starting to go (particularly given the mileage). You've had the car a while; do you have any sensation that the car is slower than it was, or revving higher than it should be for the road speed?

It's revving fine and driving perfectly apart from the loss of power problem and when I loose power the revs drop according. I've been waiting for the clutch to go myself because of the mileage but I'm told it's still fine - that was also one of the things the AA and my own mechanic checked. I will mention it the mechanic again though to be sure.

The cat was destroyed by a misread service sheet - the mechanic didn't do the spark plugs - and the symptoms of that were similar enough to give me an awful fright when this started so I'm eager to find the problem before it causes any damage. Not to mention the fact that I was in the outside lane overtaking someone and had to cut across 4 lanes of traffic while loosing power to get off the motorway before the car died!

My mechanic is going to replace the fuel pump tomorrow. He didn't give me the exact codes but he said the same ones were popping up for the bank that made him think it was the O2 sensor or crankshaft sensor and the fuel pump was the next logical step. Fingers crossed I guess...