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Discussion Starter #1
i know this kinda sounds stupid. My a/c works fine, the air comes out fine, but only if i shut the passenger vents off. If i open them, the vents dont blow very hard on the drivers side, but the passenger side blows harder than the driver side, i even did the experiment of sitting in the passenger side, and it seems to blow harder.. Is there any reason why this is? I notice as well, the a/c doesnt blow cold 100% of the time, it feels like itll blow a little lukewarm for a few seconds then start blowing cold again, but the air isn't "ice cold" Do our a/c systems just suck?
 

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The reason for the uneven blowing may be becasue the blower itself is on the passenger side, I'm not really sure where the inlet to the duct is, but if it is closer to the passenger side, which it probably is, the air is wanting to escape at the first point it comes to, which would be over there. Since when you close the passenger side vents, you get more air out the driver side makes sense b/c you are creating a smaller area for the air to escape, namely all on the drivers side.

The reason for the uneven coolness of the air: if my switch is set to max ac, it will run cool for a bit then warmer, back and forth. But if mine is on norm ac it will run cool constantly. Look into that, I don't really know why it does that, but it does on mine anyways. Hope this helps

Joe
 

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The Parts Guy
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whitecoug said:
I'm not really sure where the inlet to the duct is
The HVAC box blows the air to the center of the dash. From there ducts carry the air to the various vents. Here's a picture of the back of a 94-97 dash.



-Rod
 

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Maybe the drivers side is more restrictive! Are there any aftermarket blower motors we could install that turn faster? I know for 80s jeep wranglers, they install s-10 blazer blowers or something. I think I ran across that back when I had a g/f who had a jeep. Ideas?
-Rob
 

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The Parts Guy
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I don't know of a better blower motor, but I sure would be interested in one.

-Rod
 

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Discussion Starter #6
so theres nothing wrong with my a/c then? The one on the driver side near the door doesnt hardly do anything.
 

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Discussion Starter #8
two word to that answer, hell no. It gets way too hot over here to do that. Im in the central valley of california, its basically in irrigated desert. Last year we had like 17 or somethin days in a row of over 100F, it was horrible it never cooled off....
 

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MY 2 cents.
Mine will freeze you out of the car on max AC, so I think something is wrong.
The getting warm then cold sounds like you may be just a little low on freon. Have the level checked. A quick way to check yourself is turn the AC on max and check under the hood to see if the bigger AC line is cold and sweating like crazy. If it's just cool with no sweat, probably low freon level. If it's cold and sweaty, could be a bad pressure switch making it cycle to often or for to long.
Another thing to check is the vacuum from the engine. My 91 Dodge spirit has a vacuum check valve on the firewall and when it went bad the AC would slowly change to the floor vent and get hot as the RPM's went up. Bring the throttle back to a reasonable level and it went back to vents with cold air.

As far as the vents, sounds like an obstruction (foam came loose?) or a vacuum operated valve may be sticking or not getting any vacuum.

Hope this helps,
Rob
 

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Discussion Starter #10
last year, the a/c stopped working and it was a low pressure switch, and i got it replaced. We checked the freon level with one of those recharge kits, and the freon level was fine.
 

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I still think checking to see if the line is cold and sweaty is still a good idea and cheap. If this check passes, I'd take it in or wait for someone with more AC experience to reply. (I do have a fair amount)
By the way too much freon will also cause cooling problems.
thanks,
Rob
 

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Discussion Starter #12
when i was coming to school today i ran the max a/c and it blew cold the whole time, maybe im just trippin.....
 

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For what it's worth (or here's my 2¢ worth), here's a test from the 1997 Service Manual. Pinpoint Test A has about 21 steps in it, so have fun reading it.



PINPOINT TEST A: IMPROPER/ERRATIC DIRECTION OF AIR FLOW FROM OUTLETS

A1 CHECK SYSTEM AIR FLOW

NOTE: The air handling system is designed to provide Defrost when no vacuum is applied to any of the three vacuum control motors. This is done to prevent a situation where Defrost cannot be obtained due to a system vacuum leak. Instead, a leak in the vacuum control circuit will send all air flow to the defroster outlets. This condition may occur during acceleration (slow vacuum leak), may exist at all times (large vacuum leak) and may happen only when certain specific functions are selected, indicating a leak in that portion of the circuit.

With engine running and heater blower motor switch on high, check system airflow in each A/C control position to determine which position(s) have incorrect air flow. Refer to vacuum diagram for Manual A/C Heater System or Semi-Automatic Temperature Control for correct system air flow.

Is air flow only from the defroster outlets for all positions?
Yes
GO to A2 .
No
GO to A12 .

A2 CHECK VACUUM SUPPLY HOSE
Check vacuum supply hose to be sure it is connected to both the engine manifold and vacuum check valve.

Is hose disconnected?
Yes
RECONNECT hose. GO to A1 .
No
GO to A3 .

A3 LEAK CHECK VACUUM SUPPLY HOSE
NOTE: The vacuum hoses used in the passenger compartment control circuit are constructed from PVC plastic material. The vacuum hoses used in the engine compartment are constructed of Hytrel. Because of the materials used, the vacuum hoses should never be pinched off during diagnosis to locate a leak. Use Rotunda Vacuum Tester 014-R1054 or equivalent to locate vacuum leaks. A wood golf tee can be used as a plug when it is necessary to plug one end of a vacuum hose for leak test purposes.

Disconnect vacuum supply hose from engine manifold fitting and from A/C vacuum check valve.
Plug one end of hose and leak test with vacuum pump.

Does hose leak?
Yes
SERVICE vacuum hose. GO to A1 .
No
GO to A4 .

A4 CHECK SUPPLY HOSE FOR BLOCKAGE
Disconnect black supply hose from A/C vacuum check valve. Connect vacuum tester to supply hose and operate tester as if pulling a vacuum. If tester can pull a vacuum, hose is plugged. If tester pulls a partial vacuum, hose is restricted.

Is hose plugged or restricted?
Yes
REPLACE supply hose. GO to A1 .
No
GO to A5 .

A5 CHECK VACUUM CHECK VALVE
Check A/C vacuum check valve for correct installation by removing the reservoir hose and the control assembly source hose (one at a time) from A/C vacuum check valve and check for vacuum. Engine must be running for this test.

Is vacuum available at both check valve ports?
Yes
RECONNECT both hoses. GO to A6 .
No
REPLACE A/C vacuum check valve. GO to A1 .

A6 LEAK TEST VACUUM CHECK VALVE
Check Vacuum Tester and hoses for leakage.
Remove A/C vacuum check valve from vehicle. Connect two hoses and a Tee fitting to outlet ports of A/C vacuum check valve. Connect Rotunda Vacuum Tester 014-R1054 or equivalent to Tee fitting.

Pump 51 kPa (15 in-Hg) vacuum on A/C vacuum check valve and observe gauge reading.

Does check valve lose more than 3.37 kPa (1 in-Hg) vacuum in one minute?
Yes
REPLACE A/C vacuum check valve. GO to A1 .
No
REINSTALL A/C vacuum check valve and GO to A7 .

A7 CHECK VACUUM RESERVOIR
Connect Rotunda Vacuum Tester 014-R1054 or equivalent to A/C vacuum reservoir tank and bracket and leak test reservoir. Reservoir must hold vacuum.

Does reservoir leak?
Yes
REPLACE A/C vacuum reservoir tank and bracket. GO to A1 .
No
CONNECT hose to A/C vacuum reservoir tank and bracket. GO to A8 .

A8 CHECK SUPPLY HOSE
Remove climate control assembly. Refer to Section 12-03A.
Disconnect and plug black supply hose at A/C control. Disconnect other end of supply hose from A/C vacuum check valve and leak test hose with vacuum tester.

Does supply hose leak?
Yes
SERVICE hose. GO to A1 .
No
REMOVE plug and RECONNECT vacuum hoses. GO to A9 .

A9 CHECK CONTROL ASSEMBLY
Disconnect vacuum harness at in-line multiple connector near A/C control. Plug all vacuum hoses except black. Connect vacuum tester to black hose. Select each function position, apply 51 kPa (15 inches Hg) vacuum and check for vacuum drop. Drop should not exceed 3.37 kPa (1 inch Hg) vacuum per minute for any function position.

Does drop exceed 3.37 kPa (1 inch Hg) vacuum per minute?
Yes
NOTE function positions where vacuum drops. GO to A10 .
No
GO to A14 .

A10 LEAK TEST CONTROL ASSEMBLY
Remove vacuum harness from A/C control. Connect vacuum tester to control supply port and plug control port that indicated a leak in Step A9. Select function positions noted in Step A9 and apply 51 kPa (15 inches Hg) vacuum after selecting each position. Vacuum drop should not exceed 1.68 kPa (1/2 inch Hg) per minute.

Does vacuum drop exceed 1.68 kPa (1/2 inch Hg) in one minute?
Yes
REPLACE A/C heater function selector switch. GO to A1 .
No
GO to A11 .

A11 LEAK TEST JUMPER VACUUM HARNESS
Plug one end of vacuum hose that indicated a leak in Step A9. Apply 51 kPa (15 inches Hg) vacuum to hose and observe vacuum gauge. Vacuum should not drop.

Does vacuum drop?
Yes
SERVICE vacuum jumper harness. GO to A1 .
No
CHECK connection of vacuum harness to A/C control for leak. SERVICE or REPLACE vacuum jumper harness. GO to A1 .

A12 EVALUATE SYSTEM AIR FLOW
Repeat Step A1.

Is the air flow in step A1 correct for each function position?
Yes
GO to A13 .
No
GO to A14 .

A13 ISOLATE LEAKING VACUUM CIRCUIT
Repeat Step A1 and accelerate engine speed for each function position.
Does air flow go to defrost during acceleration?
Yes
GO to A18 .
No
GO to A14 .

A14 REVIEW VEHICLE HISTORY
Check history of operation with owner.

Did system function properly prior to this complaint?
Yes
GO to A17 .
No
GO to A15 .

A15 CHECK VACUUM HOSES
Check each vacuum hose to be sure it is not plugged.

Is a hose plugged?
Yes
REPLACE vacuum hose. GO to A1 .
No
GO to A16 .

A16 CHECK VACUUM HARNESS
Compare vacuum hose colors in each vacuum harness to the vacuum diagram.

Do the hose colors agree with the schematics?
Yes
GO to A17 .
No
REPLACE vacuum harness. GO to A1 .

A17 CHECK VACUUM CIRCUIT
Check vacuum circuit for pinched or kinked vacuum hose.

Is hose pinched or kinked?
Yes
SERVICE vacuum hose. GO to A1 .
No
GO to A18 .

A18 CHECK VACUUM CIRCUIT CONNECTIONS
Check each vacuum hose connection to determine if it is partially connected or disconnected.

Is a vacuum hose connection disconnected or partially connected?
Yes
RECONNECT hose. GO to A1 .
No
GO to A19 .

A19 CHECK VACUUM HOSE
NOTE: Refer to Section 12-03A to access vacuum control motors.

Disconnect both ends of vacuum hose in suspected circuit. Plug one end and leak test with vacuum tester.

Does vacuum hose leak?
Yes
SERVICE hose. GO to A1 .
No
GO to A20 .

A20 CHECK VACUUM CONTROL MOTOR
NOTE: Refer to Section 12-03A to access vacuum control motors.

Check vacuum motor for leaks with vacuum tester.
Does motor hold vacuum?
Yes
GO to A21 .
No
REPLACE vacuum control motor. GO to A1 .

A21 CHECK VACUUM CONTROL MOTOR INSTALLATION
NOTE: Refer to Section 12-03A to access vacuum control motors.

Check attachment of vacuum control motor arm to damper door.

Is vacuum control motor arm attached to door or door crank arm?
Yes
CHECK for binding or damaged damper door. SERVICE or REPLACE damper door. GO to A1 .
No
CONNECT vacuum control motor arm to door and check operation. GO to A1 .
 

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i have the same problem of my ac blowing harder on the passenger side than the driver side. but my moms fiance, a 30+ year ford tech, he does nothin but AC work now, and he hasnt ever found anything wrong. i know sometimes on long trips, when im running my car on max ac, the blower will stop blowing as hard. his explanation, the ac lines are freezing over from being so cold. but, he knows all the little tricks to get the ac really really cold. i think last time i checked, at the vents, my car was at like 34* F.
 

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Turn on the A/C
open the hood
run the RPMs up to about 2k and watch the A/C clutch
if it engages and disengages intermittently while at 2k, then you are probably low on freon (pressure switch reading isnt high enough). But it could also be turning it off because pressure is too high. I dont know, I have mixed feelings about my A/C though. Dark *** tinted windows help! :)
-Rob
 

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Discussion Starter #16
well when i was in the parking lot i rolled my window down, revved the engine to 2k, the compressor kicks on for about 15 secs, then disengages for about 4, then kicks back on, repeat.....my dad said that this is normal, i dunno about what u guys have to say...
 

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Discussion Starter #17
97mn-12 said:
he knows all the little tricks to get the ac really really cold. i think last time i checked, at the vents, my car was at like 34* F.
oh ya what what trick is that? Id like to know:D
 
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