What to do 2000 Pontiac Grand Am its overheating and leaking antifreeze coolant but I have replaced the water pump thermostat radiator And you had a new head gasket put in about 1 yr ago?

If your 2000 Pontiac Grand Am is still overheating and leaking coolant despite recent major repairs (water pump, thermostat, radiator, and head gasket), you're facing a serious problem that requires professional diagnosis. Replacing those components usually solves overheating issues, so something else is amiss. Here's a breakdown of possibilities and what to do:

Possible Culprits (beyond what you've already replaced):

* Cracked Cylinder Head or Engine Block: This is a significant and expensive problem. A pressure test of the cooling system is needed to determine if there's an internal leak in the engine itself. A cracked head or block often doesn't show external leaks easily.

* Head Gasket Failure (again): While unlikely so soon after replacement, it's possible the previous head gasket job was faulty or the engine block was damaged and contributed to the failure. This needs a thorough investigation.

* Warped Cylinder Head: Overheating can warp the cylinder head, leading to leaks even with a new gasket.

* Cooling System Leaks Elsewhere: Look very carefully for tiny cracks in hoses, the radiator itself (especially at the seams), or even the heater core. Sometimes leaks are very subtle, especially under pressure. A dye test can help find hidden leaks.

* Faulty Radiator Cap: A faulty cap can prevent proper pressure buildup in the cooling system. While this usually leads to boiling over rather than leaking, it's worth checking.

* Incorrect Coolant Mix: Using the wrong coolant or a mixture with improper concentration can cause corrosion and damage the cooling system.

What to Do:

1. Don't drive the car: Continued driving with overheating can cause catastrophic engine damage.

2. Professional Diagnosis: Take your Grand Am to a qualified mechanic specializing in older vehicles. They can perform a comprehensive pressure test of the cooling system, inspect the engine thoroughly, and identify the source of the leak. Mention all the recent repairs – this is crucial information.

3. Pressure Test: This is the most important test. It pressurizes the cooling system to reveal leaks that aren't visible when the system is cold.

4. Exhaust Gas Test: This test checks for exhaust gases in the coolant, a telltale sign of a blown head gasket.

Avoid further damage by NOT driving the car until a professional diagnoses the problem. The cost of a proper diagnosis is far less than the cost of a major engine repair or replacement.