trd6209

Well, I was traveling from Tucson, AZ to San Antonio, TX (approx 880 miles) and all was going great. I was getting a good 21-22 MPG keeping my air on low and my RPMs below 3250. About 260 miles west of San Antonio (population 5), I smelled burning rubber. I pulled off the road and my AC compressor belt broke. All else was ok so I completed my trip with no AC belt. I kept an eye on my guages like a pilot monitors his instruments. Paranoia began to set in and I started noticing every little bump, smell, or vibration. It was 9:30 PM and I was in the middle of nowhere. My gas mileage sucked for the last 260 miles and I noticed that my Coolant Temp guage was bouncing. It was bouncing from mid range to the low range. I was a little confused by this since I was running 78MPH on I-10 so I figured that the temperature was more than stable so the needle fluctuating was a bit of a suprise.

I made it the rest of the way and the next day I went and bought a new set of belts (I'll never leave home without them again...I had tools, but no parts) and I pulled the radiator fan and clutch to install the new belt. I got everything back to gether and now my truck idles at about 1400 RPM and it takes my engine a good 3-4 minutes of driving before my coolant temp needles moves off the peg. After that, all of my indications are normal with all guages at normal operating range. I reset my EFI C/B to no avail just to satisfy my curiosity because it had fixed other weird problems in the past and that had no effect. All indications point to my thermostat being stuck open, but I am looking for some second opinions. I have to make the trip back in about 5 weeks and there's nothing between San Antonio and El Paso but 560 miles of open space with the occasional exit that leads to nowhere. This is not the best place to have a problem. Any ideas??

WatsonMD

With the truck cold/cool - like first thing in the AM after sitting all nite - pull off the radiator cap. Start it up. If there is coolant flowing and not sitting still, the thermostat is stuck in the open position. Time to replace it.

The engine is designed to operate at an optimal temp and the thermostat is designed to keep it there. Thus, gas mileage can deteriorate if the coolant circuit doesn't allow the engine to get to operating temp quickly.

Best of Luck
Andrew

AgRunner06

Man that's a horrible drive. I made a trip this summer with a friend of mine in his F250 Powerstroke pulling an 18ft trailer from Austin, TX to Wilcox, AZ. We had to go pick up my bro who was broken down coming back from Cali (it was a heep). We made it there and back in 28 hours. Talk about a rough trip. But yeah, you definitely don't want to get stranded out there.

If I were you, I'd go ahead and replace the thermostat. It's inexpensive to replace and easy. It seems weird that the thermostat would go from mid range to low. I think I can explain the loss in gas mileage though. When the vehicle is operating under the normal temp, the computer will richen the mixture thus killing your mileage.

Good Luck

:bounce2: