My glow plugs test good but are not functioning the light comes on for a second then goes off I'm only getting 1 volt to the batteries wires to the relay. ?

 

Something is wrong if you're only getting 1 volt from the batteries to the relay.

Not sure why you started a new thread on this, but you need to figure out whats up with the wiring.
Maybe post of picture of what you have so we can help you troubleshoot. There shouldn't be an inline fuse, and if there is, a previous owner has screwed something up. I'm pretty sure that there are some pictures of how stuff should be in the glow plug sticky that might help.

 

I will take a pic tonight it is a 4 pin rectangular connection with a relay looking thing plugged in. I referred to it as an inline fuse. Now I should check the wires right out of the battery to know that it is the fuse or a wiring problem. Also there is a circular connector by my negative battery unplugged was when I got it. I'll take a pic of it to.

 

Hurray! Found a bad connector. Now has 12 to relay 11 on ignition terminal and sending out 10 to the glow plugs. Acceptable right?

 

Hurray my glow plugs are now cycling had to repair a bad connector and everything is now working. HOWEVER, now I need help as the oil pressure gauge has quit. I think I probably knocked it loose. Where is it at?

 

Oil pressure sender is at the top rear of the engine slightly towards the passenger side.

 

Also my temp light is on constantly cold or warm. My gauge shows its fine but the light is on regardless. My oil gauge doesn't move is why I asked is there a way to test sending unit and wiring?

 

My glow plugs are now only working some of the time. My relay was not activating sometimes and it smelled hot and smoked a little. I had 12 on battery terminal on relay. 11 on ignition. And 7 where it sends the power to plugs. When it did work the click to start would go out and it would stay buzzing. The zigzag metal piece on relay was hot as well

 

read the sickies................there are two voltage sources. one high current and one low current...they never come together... there is no connection to any temp sender in the late model system... the controller (see's) the temp of the glow plugs (whole engine) by measuring the resistance of the group of glow plugs, this is how the controller Knows when one or more of the glow plugs is not working...the WTS light is not a indicator of power to the glow system. when two many glows are burnt out it will not send power to the glows at all if when plugged in it starts right up it is a glow plug problem..there is only a fuseable link in the one high current wire that comes from the batt post of the start relay..the other power source is the same circuit as the fuel shut off solenoid. all connections must be clean..

 

Ok I'm running and starting good now. I'm now in need of e4od help. It won't shift out of 2nd. Fluid seems fine. So mine is a 1990 what should I check?

 

I would first search to see if others have had the same problem. If you don't find the answer, start a new thread since the e40d has nothing to do with glow plugs (the thread title...)

There is a lot of troubleshooting, but I never pay attention to those thread since I have a zf5 (manual transmission). One thing that sticks out, is your tachometer working? is the the overdrive light flashing?