[casioqv]

It's possible that the base of the glow plugs would not heat enough to detect with your infrared thermometer. The first thing to do is check with a multimeter if they're getting power when you first put the key to run. It's very unlikely that they're all burned out, so you can run them just for testing purposes by providing them power with a normal jumper cable for about 10 seconds, disconnecting it, and then quickly firing up the engine. You'll need a circuit diagram and a multimeter to figure out *why* they're not getting power if they're not. It could be just a corroded terminal, disconnected or bad temp sensor, bad relay, etc.

Using starter fluid on these engines is a huge no-no and can cause major damage: broken rings, etc. It should *never* be used in any situation on a D24. If you have a manual transmission, roll starting downhill in 3rd gear will get even the lowest compression cars without good working glow plugs running as long as they're getting fuel and timed properly. After using ether, you should do a compression check to see if you've broken any rings.

If the diesel has gone bad, no additives will help- but if it's already mostly empty you might be okay just filling the tank the rest of the way with new diesel, and keeping several spare filters handy. I'd probably siphon out the old fuel anyway and replace all of it.