RE: Glow plugs, How hard are they to replace?
First you may want to check to make sure the glow relay is functioning.. But, a more common problem on the earlier PSD's was burning at the valve cover (UVC) gasket connection/s (outer most wires/pins on each connector) andglows can drop off line if a connection is lost.. Look at the valve cover connections a see if you see evidence of high heat, melting/bulging at the connectors.. If they look OK, you can unplug the connectors and ohm test the individual glows and prove out circuit continuity through the outer cover connections for opens ect. without pulling the valve covers.. There's always a chance the stub harness are toast inside the covers too, or a failing or loose due to heatUVC connector/connection, and not actually a dead GP.. Not a terrible job to replace the GP's, but the UVC gaskets, and harness's can be a few bucks, more so in comparision to the cost of the GP's if burned on both sides..
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