Hey yall. I have a 98 subaru legacy outback limited. 155,000 miles. I just replaced the fuel filter, plugs, wires, air filter, coil, A/C belt, alternator belt and ignitor. Now the engine runs really well except the speedometer ocilates or doesn't work at all and the car randomly cuts off. There are no CELs. It restarts no problem. It seems there may be an electrical short????

 

Also if my belts are to loose would that cause it to cut off??? Or is the speedometer and engine cutting off related?

The problems you're having don't sound like something that would have been caused by your work. It may just be a coincidence.

 

Like you suggested, I'd check the electrical for a short and check the speed sensor's resistance.