glow plug realy question

[DUK TRUK]

My truck keeps blowing the #30 (30 amp) fuse when it gets real cold or wet. It usually will start fine but will blow the fuse while warming up or driving down the road. Would this be a bad glow plug relay? Does a glo plug relay intermittenly work until they quit or do they just die. There are other items in the manual this fuse operates could it be anything else?

[Motown Fire]

What does the manual state that runs on that fuse??? I don't have my book handy or I would look for ya.

[DUK TRUK]

I am at work right now and the truck is in my barn. I dont have the manual in front of me. From memory I think it says glow plug,wastegate,fuel delivery. Real vague manual info!!!!!

[stewy]

On my 99 fuse #30 was a micro fuse under the dash and when it blew it was the fuel heater in the fuel bowl ( the wire was broken and shorting out) Just unplug the heater at the back of the fuel bowl. If it is your fuel heater blowing the fuse you should also lose your wait to start light, good luck.