Just purchased a sapphire 4x4 on a j plate in black, I was told by the garage that it was standard with only 55500 miles from new, the car checked out on hpi and the service history and seemed the real deal & to be fair the car is as tight as a drum and interior and exterior is in mint condition, got the car home & 3 days later i found a concealed 'in car boost controller' under the dash a small playing card pack size device with 2 twist dials and a small screen, to be honest this made me feel sick! Having said this i am really made up with car having saved my hard earnt for 3 years, need some basic pointers on the following:

Based in wigan, best place local for servicing and tune up. Need to figure out what has been done with the car/chip/ecu etc. When i turn on the boost controller & change the settings it goes like no other car i have owned and i have had some fast cars.

Car is having a problem idling from cold start and peaking at 3000 revs, this does not happen all the time but is a worry.

Like my username suggests i am new to this cosworth game but a quick learner, any pointers would be grateful.