I assume that the cooling system doesn't leak and holds the factory pressure. (Water boils at higher temps under pressure). Also that the water pump belt has been checked. This requires you to answer a few questions for yourself. When the engine is hot and running, does the cooling fan work? Your car has an electric fan behind the radiator. If it also has A/C, turn on the A/C and look at the fan to see if it's running. I would check the fuse and also the fan relay if it isn't.
Also, you don't say which engine you have, but the 3100 V6 is notorious for developing air pockets in the water jacket if the cooling system is opened (which you would have done when replacing the pump). This will keep the coolant from flowing through the radiator and will cause overheating. There is a small brass bleeder valve on top of the bypass tube that sticks out the top of the water pump housing on this engine - open it slightly by loosening the top "bolt" a couple turns with the engine running (don't remove it, and be careful of the moving belt!); if you don't get a little trickle of coolant out, there's air trapped in your cooling system. With the engine still running, leave the valve open and add coolant until a steady trickle does come out through the valve (not just a little foam). Then close the valve and add enough additional coolant to bring the bottle up to the full line. Work quickly, the engine will get hot fast with the pressure cap off. Good luck.
The engine is overheating.
a 2002 Alero could have several problems causing the overheating. Thermostat, water pump, or clogged radiator issues are the most common causes of overheating.
air conditioner for1994 Chevy Beretta not working is there a senor that could be bad. system is charged.
Valves will clatter if the engine is overheating.Valves will clatter if the engine is overheating.
The 1988 Beretta can run hot for several reasons. The Coolant could be low, the thermostat stuck, the water pump is bad, or there could be a blown head gasket.
A warning on the dic showing an engine power reduce, indicates that there is an electrical problem with the Chevy Malibu. These issues could be worn or damaged sensors, wiring issues, a weak battery, engine overheating or stored codes that could be causing the warning.
Several possibilities - from easiest to most expensive: Faulty or inoperable radiator cooling fan - causing overheating. Faulty thermostat - causing overheating. Water pump failure - causing overheating. Blown head gasket - allowing exhaust gasses to escape into the cooling system and expelling the coolant.
Could be low on coolant.
Could be the throttle position sensor
take it to a local shop that reads codes for free... could be a sensor is out
The transmission for the 1996 Chevy 3500 could be jumping from overdrive for several reasons. The transmission could have a vacuum or electrical problem causing it to come out of overdrive. Or, there could be an internal valve problem causing this to happen.