2.5 v6 Misfire please help
Hi all and thanks in advance for any advice... my problem is as follows.. I recently purchased a 2001 156 2.5v6 sportwagon which until recently was running like a dream until I put it into a so called Alfa specialist, who for the time being will remain nameless. It was due a timing belt change so I booked it in and had the timing belt and tensioners replaced as well as a new set of plugs (NGK) the correct ones... since returning from the garage it has developed a misfire at idle as it is over fueling, it is ok when it is started from cold due to the need for the extra fuel, however when the engine is warm it idles very rough and smells strongly of fuel. I took it back to the garage and they checked it over and couldn't find any faults!! the engine management light has come on, so I took it back and they hooked it up to their diagnostic machine, which diagnosed the problem as being 3 coil packs on cylinders 1,2 and 3... I then had them order and fit 3 new coils only to get a phone call to say "ok sir that's the coils fitted, it's not any better but thats £250 please". I F*****G don't think so!!!
If anyone can offer any advice I would be eternally grateful as this is driving me round the bend... Thanks