1998 Dodge 1500 truck. 318 5.2V8 Magnum.
Question: Having Large gas usage problems and many codes replaced the o2 sensor, water temperature sensor, spark plugs and wires and distributor cap still have not fixed problem. Was wondering what could be the problem and how to fix it. The vacuum seems to be ok there is no restriction in the exhaust. The o2 sensor p0138 was on the pre-catalyst sensor came on saying high voltage. Wondering solution to problem the oxygen sensor was replaced by a mechanic.
Answer: A common thing for a vehicle to burn too much fuel and getting very bad gas mileage is a bad fuel pressure regulator. On your Dodge truck in particular it is located on top of the fuel pump assembly. This regulator could be bad allowing the fuel pressure to be too high. This can cause the SES light, hard starting, blowing black smoke when you accelerate, hesitations or even catalytic converter failure. It is also possible that an injector or more than one are stuck open and dumping too much fuel into the cylinders. Have the pressure checked to make sure it is within specifications.
Dodge Ram Overheating
2003 Dodge Ram. Engine Size 5.9
Question: my pickup overheats after 4 miles. I have replaced the water and the thermostat. i was told possible faulty therm. i was also told that the radiator might be plugged. It idles fine, but i don't want it getting hot. What could it be?
Answer: overheating can be cause by a lot of different things. A water pump that does not have enough flow, a plugged or partially restricted radiator, air in the cooling system caused by leaking head gaskets or a cracked cylinder head, radiator or A/C condenser plugged externally with dirt and debris, plugged coolant passages internal to the engine, etc. First make sure the fan is working properly. Next, run the engine with the radiator cap off, when the temperature gets near 190° look for coolant flow through the radiator. Also look for air bubbles in the antifreeze.
Air bubbles are a sign of a blown head gasket or cracked cylinder head. You can also buy a test kit at your local parts store to check the coolant for contamination of combustion gases. Do a pressure check on the system to make sure there are no leaks. Leaks will also cause air pockets in the system. If your engine has a lot of miles on it, there could a be restriction in any of the heater hoses. If you do not see coolant flow through the radiator shut the engine off and feel different areas of the radiator see if some areas are cold and some are hot. This would show restrictions in the radiator.
