Hi guys, hope you can help.

I've got a Focus 1.8 Zetec on a Y plate with about 93,000 miles on the clock.

Over the last month I've been experiencing a loss of power whilst driving - no particular pattern with regards to the different gears etc. I took it to the garage when I had the MOT and service done about two weeks ago and they did a diagnostic check - nothing showed up so they said when it gets worse to take it back. It's getting worse - last time I was driving it there was a burning smell coming from the engine. I've taken it today and they've said there's still nothing showing up, but they think it could be the cat convertor - nothing much appeared to be coming out of the exhaust when they tested it again which they said is a sign it could be the cat convertor.

They've said they can change it but of course they have told me it could be - it's a bit expensive a job for them to do on the off chance it could be that. Any ideas or feedback would be much appreciated.

Chucko

It does sound like a plugged cat. There are a couple of ways a garage can check it if I remember correctly. One checking the vacuum at the air intake somewhere and the other is by removing the oxygen sensor from the manifold and applying a low pressure gauge to the hole whilst holding the revs at 2500 rpm. Not sure what the reading should be, but you may need to get another garage to run a check on it.

It may also be worth putting some Cataclean in your tank to try and clear it, but it depends on the type of blockage you have. If the carbons have solidified it may not shift it, but if it is just sooted up, it may work.

Hi btmaldon, that's great thanks for the reply - I'll get some of the Cataclean first and then try another garage.