2005 cobalt leak @heater core cover under dash

It is more than likely the heater core is leaking and needs to be replaced.....if this helps please leave rating on this post and good luck.

is your heater putting out heat. it may be your heater core.

Well if it leaks after a heavy rain, then suspect your windshield seal is simply bad and needs resealed.if it is anytime, then it sounds like you have either a heater core leak or a hose to the core.All that is contained under the dash on the passenger side.You will need to take off the plastic covers under the dash on that side then get up under the dash with a flashlight and look while the car is running.Let it get hot and turn the heat on also then just look for the leak.if it is really wet you wont have to wait long with the car running and the heat one to see the leak.

Your heater core has developed a leak - the wetness on the passenger side carpet is engine coolant
from a heater core leak, or a leak in one of the two hoses connected to the back of the heater core.
Your strategy: disassemble dash down to heater core, determine whether you'll need a new heater
core or new hose (or new hose clamp), then replace the offending part.

If coolant is leaking from the heater core into the interior or through a weep hole out of the car your heater core has sprung a leak.
Most vehicles have easily accessible heater cores, only requiring removal of a panel under the dash or hood to gain access. On the '97 Skylark it's accessible under the dash.

• Disconnect the negative battery cable.
• Drain and recycle the engine coolant.
• Raise and safely support the front of the vehicle.
• Detach the drain tube, then disconnect the heater hoses from the core tubes.
• Carefully lower the vehicle.
• Remove the console if equipped.
• Unfasten and remove the sound insulators, console extensions and/or steering column filler, as required.
• Remove the floor or console outlet ductwork and hoses.
• Remove the heater core access cover.
• Unfasten the heater core mounting clamps/bolts, then extract the heater core from the vehicle.

To install:

• Install the heater core, then secure using the clamps/bolts.
• Fasten the heater core cover.
• Connect the outlet hoses and ducts.
• Install the sound insulators, console extensions and/or steering column filler.
• Raise and safely support the vehicle.
• Install the drain tube and connect the heater hoses to the core tubes.
• Carefully lower the vehicle.
• Connect the negative battery cable.
• Fill cooling system and check for leaks. Start the engine and allow to come to normal operating temperature. Recheck for leaks and check coolant level. Add if necessary.

sounds like heater core is leaking and running out of the a/c evaporator drain

are you sure its just water or could it be antifreeze from the heater core

If leaking coolant under dash on passenger side floor broad it's your heater core. Call's for 2.8 labor flat time to remove heater core, in some case's you'll have to recover, evacuate and recharge your A/C system to remove your heater core.Sit under dash on passenger side.

Three things can cause this.A leaking heater core,leaking windshield(when it rains,or has been washed),and sometimes not often the AC drain plug can be clogged.I would go with the heater core,look under the dash you will see a black plastic box with 8mm screws about 6-10 of them remove them from the bottom first and gently pull on the cover you should get water running out.Replace the heater core,if water present.

This happened to me many different times. The dealership kept telling me that it was condensation and that I needed to get a new cabin air filter. I went to another shop that said it was a major issue that needed to be taken care of at the dealership under warranty...

Finally, I complained at the dealership that this was a repeated problem. They looked at what they called a "check sheet" (recalls that they don't notify the customers of) and determined that there was a certain gasket that was never put on at the factory.

They put on the gasket, and I haven't had the problem since.