I need to know where the a/c condensation tube is located. A diagram or picture would be great. Leak coming in on passenger side.

Most likely it is the condensation from the air condition building up. There is a small tube under the car that the condensation is supposed to drain through, but it is easy for the tube to get clogged by debris causing the condensation to overflow onto the floor inside. The best way to clear it out is to go under the car and locate the tube, it will be on the passenger side underneath. Use compressed air to blow the debris out of the tube.

98 grand cherokee limited 5.2L same problem found leak not from heater box but from drain mount on firewall under the glove box not behind it. drain line should be located behind right front tire in the frame. Turn your wheels hard left look inside fender well right side towards back side. hole in frame where drain line should come out.

Robert,
Using a cooling system pressure test tool to pressurize the entire cooling system, a heater core will leak into the HVAC [heater, ventilation and air conditioning] box [located under the dash board]. Once coolant leaks into this box, it will either drop onto the carpeting on the passenger side front floor OR drip out the condensate tube [where the A/C condensate water leaks out under the truck] The condensate tube is a rubber pipe located on the lower end of the passenger side firewall.
Leakage into the passenger carpet [most common place for it to leak] will appear as a wet carpet.
If heater core replacement is required, do yourself a favor. Buy and install a new A/C evaporator [located in the HVAC box with the heater core] at the same time. This is a big job to do. No sense replacing the heater core now, only to have the A/C evaporator fail next summer, forcing you to repeat all that labor [8 hours for a pro mechanic who knows what he is doing].

Bulletin No.: 03-01-39-011B
Date: November 22, 2005
TECHNICAL
Subject:
Water Leaks Into Passenger Compartment Through HVAC Module Condensate Drain Tube When Parked on Incline/Uphill Position (Install Auxiliary Drain Tube Extension)
Models:
2003-2006 Saturn ION Sedans and Coupes
Supercede:
This bulletin is being revised to include the 2005 and 2006 model years. Please discard Corporate Bulletin Number 03-01-39-011A (Section 01 - HVAC).
Condition
When vehicle is parked on an incline with the front end up during a rainstorm or when driving uphill during a rainstorm, water may leak into the passenger compartment through the condensate drain tube opening of the HVAC module.
Cause
Water may drain out of the cowl drain, then drain down the front of the dash panel in the engine compartment and seep into the HVAC module condensate drain tube opening. The water then collects in the heater core cover and upon acceleration may leak into the passenger compartment through the heater core cover seams.
Correction 1. Open the hood and locate the HVAC module condensate drain tube in the engine compartment on the right side of the dash panel.
Important: During installation of the auxiliary drain tube, do not make contact with the HVAC module foam gasket located at the base of the HVAC module condensate drain tube. If the auxiliary drain tube is pushed on too far and makes contact with the foam gasket, water may leak into the passenger compartment.
2. Slide the auxiliary drain tube onto the HVAC module condensate drain tube and make sure that the auxiliary drain tube is angled downwards after installation.

PASSENGER SIDE OF FIREWALL . ACCESS FROM UNDER CAR BEHIND RACK & PINION , COMPRESSED AIR WORKS GREAT TO DISLODGE BLOCKAGE

The orifice tube should be located inside of the metal AC line from the condenser. The discharge hose (from the compressor) connects to the top on the condenser (inlet). The orifice tube mounts in the bottom of the condenser (outlet to the evaporator). The outlet tube of the condenser has a 45º upward angle. If it is not in that location it will be farther out on the same line where it connects. Here is a diagram that might help.

The drainage tube for the evaporator case is plugged causing the the condensation to drain inside instead of outside the car. The car will probably need to be lifted to find the drainage tube. Use a pick to gently remove the debris blocking the tube. You must be very careful as not to puncture the evaporator core.

Check the drain of A/C condensator, its possible that is clogged; check underdash passenger side.

Good luck.

The drain tube is clogged.
It is located under the car on the passenger side, under the dashboard.
Use a straightened-out metal coat hanger wire; the twisted screw end works great for this task. Yes, you will get your face a little wet from splash, so have a dry towel handy.

Your a/c drain tube is plugged up, causing condensation from the a/c unit to leak into the front passenger side area. You need to go under the car at that approx. location, you will find a drain tube behind the pass. side front wheel. Run a small wire (like a wire from a coat hanger) up the tube to dislodge any goop plugging the line.