While the glow plugs was fine, the heater is junk. It did well for a week, then started smoking horribly. A couple more days and it wouldn't ignite. I tried putting the vacuum on the exhaust per the manual, and that didn't help. Took it apart and cleaned it out, it did good for about a week, and does the same thing again. Liquid fuel is actually dripping out of the exhaust when it is trying to light