92 945 T 120K - I had been driving about 150 miles at 65 to 75 mph. The engine lost power without any warning. No dashboard idiot lights came on until I coasted to a stop, at which the engine just stopped. Now all the lights on the dashboard came on. I was thinking it was a timing belt, which was replaced at 100K, until I cranked the engine and it started. When I gave it a little gas, it stumbled and stalled. Started right up again, but continuklally stumbled whenever I gave it any throttle. I put it in gear and idled along the side of the highway for a mile or so. After that, it responded to throttle inputs and took off. Since then it has been running kinda rough just of idle, like when driving around town at 20 mph, but performs well at speed or under acceleration. I am thinking vaccum leak, but where to look? Has anyone else had this problem? Where do I start? BTW, the engine is due for its 120K tune up. Also, no codes on OBD for fuel and ignition systems, only 1-1-1.

Any insights greatly appreciated.

SteveC