I see ur car is an 08. This is regarding the 05-06 but looks like they still have not corrected the problem according to ur post.
But first The ac drain tube is on passenger side of the firewall, near the bottom behind engine, its tough to see from the top sometimes, it usually has a short rubber hose on it pointing to the ground for drainage. Try blowing some air up into it or running wire up it to see if possible it is plugged. YOu may be lucky and thats all the problem is.
This is a rather common problem with the earlier cobalts, and looks like it still is. By the way there are several other makes of cars that have this same problem. I't not justthe Cobalt.
Now for othe fun stuff.
Bulletin #05-01-38-016B: Water Leaking on Front Passenger Side Floor of Vehicle, Water Blowing Out of Vents (Seal Heater Core Cover) - (Aug 16, 2006)
Subject: Water Leaking on Front Passenger Side Floor of Vehicle, Water Blowing Out of Vents (Seal Heater Core Cover)
Models: 2005-2006 Chevrolet Cobalt
2006 Chevrolet HHR
2005-2006 Pontiac Pursuit (Canada Only)
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This bulletin is being revised to provide the part number of the screw that is required for the Cobalt and Pursuit models. Please discard Corporate Bulletin Number 05-01-38-016A (Section 01 -- HVAC).
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Built Prior to the Following VIN Breakpoints: Model
VIN Breakpoint
Cobalt/Pursuit
67661747
HHR
6S551004
Condition
Some customers may comment on water leaking on the front passenger side floor of the vehicle. This leak would occur under high ambient temperatures and high humidity situations when the customer has the air conditioning on high. Leaks will appear to be coming from the HVAC module where the heater core cover and lower case come together. Also, some customers may comment on water droplets blowing out of the vents when the A/C is on high.
Cause
This condition may be due to water condensing in the HVAC case that adheres to the upper surface in the tongue and groove area of the lower case and then leaking out.
Correction
Install the foam gasket between the heater core cover and the lower HVAC case at the location of the leak using the procedure listed below.
•Remove the right side insulator/closeout panel retainers and the panel, if equipped.
•Remove the 5 screws (1) (HHR) or break the 4 welds (2) (Cobalt/Pursuit) from the heater core cover at the specified locations.
•Carefully pry apart the heater core cover and the lower HVAC case to achieve a 12.7 mm (0.5 in) gap.
•Install the foam gasket, P/N 15878211, using a flat rigid tool (feeler gauge shown) into the sump area (1) of the heater core cover.
•Reassemble the case using the 5 screws that were removed (HHR) or with new screws (Cobalt/Pursuit), P/N 11609829. For Cobalt/Pursuit, add an additional screw (2) at rear of sump area.
•Install the right side insulator/closeout panel and retainers, if equipped.
Parts Information
Part Number
Description
Qty
15878211
Gasket, Heater & A/C Evaporator Module Drain Tube
1
11609829 (Cobalt/Pursuit Only)
Screw
5
Warranty Information
For vehicles repaired under warranty, use:
Labor Operation
Description
Labor Time
D9714*
HVAC Case -- Reseal
0.5 hr
*This is a unique labor operation number for bulletin use only. This number will not be published in the Labor Time Guide.
GM bulletins are intended for use by professional technicians, NOT a "do-it-yourselfer". They are written to inform these technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions, and know-how to do a job properly and safely. If a condition is described, DO NOT assume that the bulletin applies to your vehicle, or that your vehicle will have that condition. See your GM dealer for information on whether your vehicle may benefit from the information
