Questions and Answers

Ford F-250 Diesel Hard Starting Q. I have a 1988 Ford F-250 with 7.3 liter diesel. It is hard starting (at least three tries) with a huge cloud of black smoke when it does start. If the engine is warm, it starts with no problem. Any suggestion? Thanks for the help. George

A. If the "WAIT TO START" light is turning off too early, and the truck was built before 11/89, then you may have an older style glow plug control module that is faulty. There was a modification that can be done to fix this.

Most likely thing is that you have one, or more, bad glow plugs. Take a test light and connect it to the Positive (+) battery terminal. Now touch the tip of each glow plug. If the light comes on, the glow plug is good. If the light does not come on, the glow plug is bad.

If you find one bad glow plug, your best bet is to replace all the glow plugs.