Where you say “Fuse in relay good” -- I have found the fuse on the relay to be defective even though it looks good with a meter [ continuity and zero voltage drop] but later found it had failed due to “ embrittlement ” which makes it work intermittently and even sensitive to temperature. I recommend you replace this ~$2 part and get a spare too. You might just find this solves your problem.

Where you say “When engine turns over get power to the 5 pins in relay ” – This is not entirely inconsistent with a fuse that has an “ embrittlement ” failure… and keep in mind that the relay is designed to continue powering the glow plugs for up to about 1 minute total time… even after the engine has started.

Where “SIXTO” says “Did you check the fuse upstream of the relay” – The glow plug relay fuse is rated ~80 amps and to the best of my knowledge IF your relay has such a flat [~80A] fuse, there would be no other fuse "upstream"… certainly none inside the fuse box on the firewall… there are none there high enough in value to supply the 50-70 amp load of the relay and glow plugs!

Try throwing a new 80A fuse at the relay… it’s cheap! You need a spare anyhow... and I would not be surprised if the old one breaks in half during removal ! What's your alturnative... big buck$ for a new relay?

Sam