Your car probably has problems with the contact point assy in the disributor. All of these old cars had this problem. The other thing that is common is for the EFI control module to have a fault. The reason your mechanic sent you to the dealer is he doesn't know anything about this car. You need the manual to properly understand even the basics of how the EFI works on these early cars and even then you can get lost in it. Take it to an old timer that has been working on them for many many years for best results! The dealer will be lost too unless the old timer still works there.
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