I think that everybody has been through a scenario like this at least once.

My brother had a surging problem with a 740 a few years ago. He took it to the local 'Volvo specialist' who kept the car for 4 weeks and replaced the fuel pumps, pressure regulator, injectors, and ECU - to no avail - and presented him with a bill for something like $1400. Needless to say, he wasn't pleased. He refused to pay the bill until the shop fixed the car properly. They asked him to give them another 2 weeks and promised that it would be ready at end of said 2 weeks. He came back to check on their progress about 5 days later, and the car was not there. Shop owner told him that he had taken it "home" to work on it in his spare time. Brother requested that shop owner produce the car and he refused. Bro called the police, reported the car as 'stolen', and suddenly shop owner was very cooperative and pleasant.

I ended up fixing the car, BTW. Wanna guess what the culprit was? The fuel pump relay!! Resoldered for $0 and the car ran like new again.

Still no clue as to where the car was for those 5 days, or what really happened to it.

I suggest that you get a Haynes manual and start doing this stuff yourself...I don't trust these so-called 'specialists.' I can tell you another story some other time about how one of them dropped my 245 off a lift...