hi guys---i have a 01 that just changed glow plugs in on friday night. before i did the job the truck ran fine, just wouldnt start when it got 30 degrees or lower without plugging it in. after i got done i left the shop hit the highway and it felt like i was trying to pull a 130,000 lb crude truck down the road. it starts and idles like a dream, and sounds fine. any ideas to what the hell is going on? i checked the air to air boots, and all the things i took off and unhooked to do the job and it all checks out ok. what did i do? truck has 97,000 miles on it. thanks!