Bit of a long read, but I can't make sense of the problem.
Some monts ago I bought a mk1 Jetta coupe from a guy down in Oregon. Bone stock with 126K on the 1.7l. Fixed up a few minor issues and started daily driving it. Around the 4th of July driving one day the fuse box began to get hot and melt a bit, turned out to be my fuel pump fuse not making complete contact and arcing. This car has melted a few fuses when I drove it up from OR, many of the fuses were the wrong amperage, there was a 30amp fuse jamed in the fuel pump slot.
After pulling the old fuse box, checking all the relays and installing a brand new fuse box I attempted to start the car and it devloped a large vaccum leak, I discovered a few of the injectors were loose and the seals were bad. Replaced all seals and cups. Went to start it and, nothing. It will start and run at high RPM's then either die or struggle really hard and it has a popping coming from the airbox.
That's where I am at now, stumped and frustrated. I don't want to tow it to a shop pay $100 and have them stare at it and tell me nothing. Hoping someone here could lend a hand.