RE: A/C blowing out the defroster.
Yes, Tim,
Those little nylon hoses are the vacuum hoses. Don't go running to the dealer just yet. There are a few things you van try yourself. All you need are a few hand tools and a torx bit to fit the ETAC module (Temperature controller) mounting screws - maybe. You can stop when you like and go to a dealer.
Unfortunately there is no picture of the vacuum connections of the A/C - heater or ETAC module (controller). But, before you check the hoses out, make sure that fuses 1, 5, and 16 in the instrument panel fuse box are OK. And, also check that the fuse for the EEC/VRCM is OK. It is located in the engine compartment fuse box - 4th hole down on the left as you look into the box. But, I dont think the car will start if this fuse is bad. So leave this as a last resort.
The hoses on top of the accumulator are for the vacuum to the EATC system and vacuum reservoir. If you follow the hoses, located on the passenger's side cowl (just below the hood), there will be a three port check valve. It is mounted on a small bracket. The rear port should have engine vacuum on it. Start the car and disconnect the rear port hose by twisting it off the valve and put your finger on the hose. There should be full engine vacuum on it. You should not hear a leak like a hissing sound comming from its connections or any part of the hose. If there is no vacuum or a hissing sound, there is a loose connection on that hose and you need to repair it or replace it. To replace it, use 1/4" rubber vacuum hose from your local auto store or if you want to keep the nylon, buy 3/16th vacuum hose and cut the nylon at the hole or break, and place a 3" piece of rubber hose between the two pieces. If that is the problem, put everything back together and try the system out. You will probably find that you've fixed the problem.
If there is good vacuum there, disconnect the black tube that comes out of the port on the front. Suck on the hose or buy a vacuum pump with a guage on it. (You can buy a vacuum pump for around $25.00 at an auto supply store). Test the connection and see if there is a leak on that hose. You are probably going to find one or the other is leaking - big time. If not, then remove the engine vacuum line at the engine and the A/C vacuum line (from the front connection) and suck on the engine hose or use the pump. Make sure that there is vacuum on the front port. Next, plug the vacuum port to the A/C port (the front port) with a rubber plug or cover it with your finger and suck on the engine hose or use the pump again. You should feel or see that the vacuum is easy to start - and then gets harder and harder to pull as the vacuum increases when the vacuum reservoir fills with vacuum (or the air is removed). When it gets difficult, take the hose out (or off) and make sure that the vacuum stays in the tank and does not come back out the engine hose. If it does, the check valve is bad,but that will not cure your problem unless it is broken and all the vacuum can escape. Let it stand about a minute and then unhook the plug from the front end of the check valve. Vacuum should be present. If not, see below. If OK, then that insures that the vacuum tank and the check valve is OK. The pump is a bit better because it has a guage on it and will show if there is a slow leak in a line or the tank. However it takes a big leak to get the problems you are having.
The manual says to start out by starting the engine and press each function button slowly, one at a time. (The buttons along the bottom of the EATC controller. - MAX A/C, VENT, PNL/FLR, FLOOR,FLR/DEF,DEF). A momentary hiss should be heard as each button is pressed. A continuous hiss at the EATC control assembly indicates a major leak somewhere in the system. If a momentary hiss cannot be heard as each function button is pressed, check for a kinked, pinched, or disconnected vacuum supply hose. Also check the vacuum check valve as above.
Next, with the engine running, check out the electronics by using the on-board self test built into the EATC control itself.
Start the engine. Press the OFF and FLOOR buttons simultaneously and then AUTOMATIC within two seconds. The test may run as long as 30 seconds, during which time the display will be blank. If it is blank for more than 30 seconds, the system has found no errors and then press the BLUE button to deactivate and restart the system before turning the key off. Be prepared and write down any numbers and let me know if you get any. If you have a vacuum leak, it will probably not show anything, but it will check the electronics of the module out.
Next, if you have not found the problem, you will have to remove the EATC or Electronic Automatic Temperature Control unit to make sure that vacuum is getting to the unit. Here is where you can decide to take the car to the dealer or not. If you have the tools or want to buy them, proceed. My guess is that the EATC module is not getting vacuum. When the vacuum is not getting to the module, the EATC vacuum motors will default to the defrost position.
To remove the EATC module, disconnect the battery ground cable. Remove the instrument panel A/C control opening finish panel by unsnapping at the bottom. Remove 4 torx head screws retaining the control assembly. (you may be able to use a small 7mm or 8mm metric socket. Pull it out as far as possible and reconnect the battery ground connection after you determine that no wiring damage has occurred. Start the car and try the test where you press each button in order to find out if the vacuum is going to the vacuum motors. If not, then stop the car and remove the battery ground cable again. Go back inside the car and remove all the electrical connectors to the EATC module. Take a 7mm (I think) socket and remove the 2 nuts from the oblong shaped vacuum connector on the back of the control unit and remove the connector. If the vacuum is present, you should hear the vacuum reservoir pull in air as you disconnect the vacuum connector. Then put the battery ground back on and start the car. Check to make sure that one port (I believe the center port)is getting good vacuum. If it is, then the problem is with the EATC module itself and it needs to be replaced.
I will bet you will find that there is a leak between the engine vacuum connection and the EATC module itself. The vacuum reservoir could also be leaking. That is located in between the right front inner fender and the shroud that covers the wheel well. In order to remove that, turn off the air suspension switch. Jack up the right wheel and take off the wheel and tire assembly. Remove the screws and push pins and fold the plastic cover out of the wheel well. The vacuum reservoir is a small round tank with one nylon hose attached to it. Use a 1/4" vacuum hose connected to the tank to check it out as before. Check the rubber adapters that go between the connections and the nylon hoses. They are a weak point in the system. They can be replaced with 1/4" vacuum hoses from an auto supply store purchased by the foot. The most difficult one is the one going through the front cowl from the check valve to the EATC module itself. If there is a break in that line, or any nylon hose, use 1/8" rubber vacuum hose and slip it over the hole, split, or break - with the rubber hose going at least 3/8" on each side of the leak. Dip the nylon hose into paint thinner containing Methly Ethyl Ketone (MEK). This will seal the mini-tube in the vacuum hose. 1/4" vacuum hose won't be small enough to seal the leak. I say Vacuum hose because it has a stronger and thicker side to it in order not to collapse when a vacuum is applied to it.
Good Luck. I think you'll find the problem quickly.
