Motorcraft ZD1A Glow Plug Review

If you have one of the old Idi diesels (I have a 6.9 in an '84 F250) then these are a must have. They're a bit more expensive than the competition, but in this case you get what you pay for.

In the summer my 86 F-250 6.9L was missing them for 6 months, all 8 burned out and had to be replaced. I even unplugged the factory glow plug switch and installed a momentary push button to prevent overuse of the plugs while the engine was running. They still didn't help. I replaced them with DieselRX spark plugs.

Fantastic glow plugs. They are best suited for your 1984 Ford IDI pickup diesel engine. They won't warp or loosen if they get too hot. They also glow pretty quickly. Here's a video of these glow plugs being tested on the dyno in the field to see how fast they light up. Very good glow plugs. Avoid others and buy these. As far as I know they are made in Germany. Check out this video of me testing these glow plugs before installing them: Locate the ZD1A film studio in the U-tube[.]