Car's been loosing power for a while but seems to correct itself, went really bad back in march so had someone to change the spak plugs for me, hey presto all was fine. I don't know if this bits relevant but my exhaust had come away from the back box so a family friend welded it back on, however as soon as I drove it the engine management light started flashing and it had no power.

Took to local garage but they couldn't get a computer reading. They said it would most lightly be the coil pack or the head gasket. They suggested changing the plugs, leads and coil pack and a cost of £200!! And they also said they'd carry out a compression test to rule out it being the head gasket. Simply don't have the money to get it done, so I changed the leads but still no joy, is my next step to buy a used coil pack and try that or should I go down a diff avenue (i don't want to waste money i haven't got) My brother who sadly lives in austrailia so isn't here to help, said the spark plugs should be fine as they were only changed in march and to check the oil tank for 'mayo' which indicates it being the head gasket, I've done this and it looks fine.

Having read another post regarding 'wet sparks' how do I carry this check out, presumably it isn't a good idea to drive the car when it's in this state!?

Any help would be great thanks, and keep it simple as I have very little car knowledge!