Hiya.. Had my '83 XJ550 Seca 550 checked out at the local shop. Running like a top! Then I put a couple of old OEM flashers on... During testing the flash didn't work for a second, and then the engine went down to 2 cylinders. Disconnecting the flashers/putting previous ones back on don't help! Any thoughts? I am an electrical donkey ...but do own a tester.