2003Chevy venture overheats QUICKLY, but is losing no antifreeze and there is no fluid getting in oil?

Question

vehicle overheats in first 5 miles, loses power also, but loses no antifreeze and do not believe head gasket is blown. Has 100,000 miles on it. Very confused

Answer 1

Either the thermostat is sticking shut or the radiator is not circulating. If you change the thermostat (that is most likely the problem) It should solve it. To find the thermostat follow the top radiator hose to the thermostat housing and change it out with a new one.

Answer 2

Assuming the air filter has been changed sometime int he near past and the water pump is pumping coolant and the catalytic convertor isn;t plugeed and creating too much back pressure:

1. The electric radiator fan isn't coming on. The thermostat that controls the fan or the fan motor might be shot.

2. The mechanical thermostat is stuck closed. This rarely occurs, they typically stick open, but I have seen this occur on hard driven motors like the LT1 motors in the Chevy Caprice Cop cars.

3. There isn't enough coolant in the system or a big bubble is in the cylinder heads.

4. The plastic coolant tank that holds the coolant under pressure has a split in the seam. Typically the seam is horizontal and the pressure will escape from the seam with no leaking unless the water level is higher than the seam.

5. The high pressure cap, radiator cap, isn't holding 15 psi and the water is therefore boiling in the block/heads.

6. The coolant is not a 50/50 mix. Pure water or pure antifreeze will overheat. The coolant has to be a 50/50 mix of antifreeze and water.

If all else fails, there is a small leak into the water jacket from one of the cylinder heads. Maybe not a head gasket leak but a minor warping of the head or a microscopic crack.

I recommend that people use the same Cadillac additive with any car or truck. These are brown cylindrical "horse pills" that are standard additive to the coolant on Cadillac motors. Last I bought some was at Kmart. I think the company name is Bars Leak. You drop one "horse pill" in the radiator for each gallon of coolant. Most cars hold only two gallons of coolant, total. One gallon antifreeze and one gallon distilled water.

Good Luck!

Answer 3

Given the limited amount of information supplied and counting it as correct I would venture to say that a possibility of two or more problems might exist. A stuck closed thermostat or possibly the cooling fan / fans are not operating. If you are in a warmer climate and are using A/C, this problem would be more noticeable. Check to see that your fans are working properly, when you reach what would be normal operating temperature, they should run, when A/C is energized, they should run. if they do, but the car still over heats, suspect a stuck thermostat. Best I can do with a hands off diagnostic. There are other possibilities to be sure, but these are easy to verify. From an ASE Master tech.

Answer 4

sounds like the condenser, I would say the thermostat, but that would not cause a loss of power, but I know that I had a similiar problem with a truck