My truck has been having a really hard time starting recently. It has been really cold though somewhere around -12. It starts fine when plugged in but after sitting at work it isn't so fun. I have one glow plug burnt out, could this cause this much of a problem just being one glow plug?

 

I don't know if one would cause that much problem, unless it's drawing all the juice from the rest. I'd get a set of all new GP's and a new/upgraded GPR. I did that on my truck a year ago and it was night and day difference. With the cold weather we have around here it's definitely worth the money, and peace of mind.

 

Try jumping the large posts on the relay next time it's hard to start and see if maybe the contacts on the relay are getting fried.

 

Just one GP wouldn't cause that. When they go bad, they open (go higher in resistance), so it would actually draw less current than the others. I agree with Dan -- check for a bad GPR.

 

my NAPA GPR would measure 12v at the load terminal but I was still having a hard tme starting. I had the Stancor for a backup so I put it in. Made a big difference.

 

My GPR is good I changed it out last year for the Stancor. I also checked it today and its getting 12.5V constant and the other post is getting 12.5 with key cycled. I changed the number 7 glow plug today guess we will see what happens.