The Mustang has the 3.8 V-6. The Tempo is the 4-cylinder that started life as a Ford inline 6-cylinder.

No, the Tempo has been unreliable from nearly Day 1. Numerous times, my old man would be someplace (generally the mall) and it just wouldn't start when he went to go home. Didn't matter what the temperature was or how long it sat, it just wouldn't start. He'd have someone come and tow it to a garage and, naturally, it then would start right up. Nobody from Ford mechanics to neighborhood mechanics could figure out what was wrong. I've had the same thing happen several times. Hence, since I work nights, I never take it to work. Believe me, when I get my Challenger, the Tempo is gone!