Ok here is the run down from before gauge fluctuation, was driving home about a block away from my house my idler pully seized up and belt broke I costed into my driveway. Replaced pulley and belt, noticed I could push down on the tensioner pully to run the belt without a wrench, didnt think much of it, checked the fluid in the radiator it was about a half a bottle empty I have had the truck for about a year and a half but never checked the fluid in the radiator, I know stupid move, so I filled it about 2 days later I was going away for the weekend 3 hour drive, about half way there the temp gauge started fluctuating out of know were only got a little past 1/2 but would keep fluctuating from 1/2 to 1/4, got to my destination changed the thermostat, added coolant drove home a couple days later temp gauge was getting up to about 3/4 know, made it home without overheating. Called around some people said temp sender, went to napa bought one then it started to over heat, went and bought another one from ford back to square 1, fluctuating1/2-1/4, decided to do the radiator, water pump, a differant companies thermostat, got everything from napa. Changed all that and flushed the whole sytem. No change in temp gauge. Bought an aftermarket temp gauge to see what it was getting to, so I eliminated the factory gauge all knew wire and new sending unit for the gauge know that one was fluctuating to from about 220-170. Was thinking maybe the tensioner pulley was bad and making the belt slip on the water pump and fan pulley creating a fluctuation, replaced that temps are between 180 -205 so it got alittle better, still fluctuating. Was wondering if it could be a head gasket so I bought a block and headgasket tester kit with the blue dye I did this test like 5 times liquid stays blue. Went out and bought a new radiator cap put that in drove for about 20 minutes no change in gauge, opened the hood and the upper hose was collapsed, went out bought an upper hose put that in and put the factory radiator cap back on seems to stay had it running outside for about an hour no collapse, burped the coolant system to get rid of the air, hooked the factory gauge back up, right back to stage 1 fluctuating between a little over 1/2-1/4. Man this sucks, thanks for reading I know itsd a long one.
Saturday, March 6th, 2010 AT 4:17 PM