Wait to start light

[TWL]

I am driving a 1996 GMC Suburban 1500 SLE with 6.5l turbodiesel. About 4 months ago in the heat of a Charleston summer the "Wait to start" light quit working and would blow the Eng 1 fuse. The check engine light came on and code for a glow plug circuit problem was read. I replaced the wiring insulation to the glow plugs on the passenger side and the glow plug relay control. Things worked as normal for a while. Now the "Wait to start" may not come on in the morning but the fuse does not blow. If I jiggle the large orange wires and red power (?) wire to the controler the dash light will come on and the engine starts as normal. I put the original controler back on and it works the same so I don't think the controler is the problem. When the engine is warm, the dash light comes on every time so I am thinking there is a problem in the hard cylindrical plastic pieces (fusible links?) which join the large orange wires to smaller wires going to the controler. Has anyone had this problem? I don't know if it's related or not , but at the same time the volume on the radio has been going crazy. Any thoughts?

[racer55]

Make sure that the glow controller mounts are clean and making a good grounding contact.

Also check the small wires that plug into the controller for an fraying or poor contact.

If a scanner is available that will display engine temp,I would try and make sure the ECT sensor is giving the correct reading.

If no scanner is available,unplug the ECT sensor in the water crossover before you try a cold start and note what reaction the glows give,it could be that the ECT is bad.

Unplugging the ECT will make the ECM think that it is -40 and cycle the glows-if this happens the sensor is suspect-AC Delco only for electrical items on these trucks.

[phantom309]

Clean all your grounds ,. crazy volume fluctuations points to grounds,.