Automotive Air Conditioning Information Forum (Archives)

Provided by www.ACkits.com

We've updated our forums!
Click here to visit the new forum

Archive Home

Search Auto AC Forum Archives

AC not working need help. newbie

ktod101 on Tue July 08, 2008 9:17 PM User is offline

Year: 2002
Make: nissan
Model: ALTIMA
Engine Size: 4CY 2.5S
Refrigerant Type: 143a
Pressure Low: 35
Pressure High: 225
Country of Origin: United States

hi
i have a 2002 nissan altima and all of a sudden the ac is not working. i cleaned out the system and recharged it the compressor is working fine. (pipes produce condensation, compressor cycles) however when i first start the car the ac throws air but it is not cold. when drive the car it throws hot air. what could be the problem.

any help would be appreciated
thanks
kevin

Chick on Tue July 08, 2008 9:20 PM User is offlineView users profile

Have to ask basic questions first. Did you pull a deep vacuum and recharge the factory amount back into the system? can you see if the compressor is engaged when it begins to blow warm. Check the clutch gap (if it was charged properly) should not be more than .02 air gap..let us know
Also, was anything added other than refrigerant and dye? no sealers?

-------------------------
Chick
Email: Chick

---------------------------------------------

Freedoms just another word for nothing left to lose

ktod101 on Tue July 08, 2008 9:30 PM User is offline

yes i performed a deep vac and recharged to factory conditions. the compressor stays on and hot air begins to blow when the car is drive. the compressor kicks on when the ac knob is turned. the clutch gap is set to the right amount. only 143 refrig was added. could it be a problem with the duct work.? or the blowers. the ac blow but not as strong as it once did

mk378 on Tue July 08, 2008 10:32 PM User is offline

Sounds like the heater core is fighting the A/C. Not sure on that exact model but there is usually a water valve that cuts off the flow of hot coolant to the heater when you set the temperature control to full cold.

U-96 on Tue July 08, 2008 11:19 PM User is offline

Quote
Originally posted by: mk378
Sounds like the heater core is fighting the A/C. Not sure on that exact model but there is usually a water valve that cuts off the flow of hot coolant to the heater when you set the temperature control to full cold.Alternatively, there can be a flap(s) that directs air either through heater core or bypassing it. If the control cable or motor or whatever controlling mechanism is broken, the flap can be stuck in the open or half-open position.
But in any case if this is the heater vs. A/C situation the system would blow warmer than ambient air when the A/C is off.

ktod101 on Wed July 09, 2008 4:42 AM User is offline

Also on another note the heat does not really work to good in the winter either.

bohica2xo on Wed July 09, 2008 12:43 PM User is offline

Time to step up for an All Data subscription for that car.

The refrigerant loop is working but you are getting significant re-heating, and poor heater performance.

That Altima has CAN bus connectivity with the HVAC system. There may be codes stored that relate to the HVAC system. The airflow is controlled by a series of doors that are actuated by servo motors. If you have the "Automatic Air Conditioner" option, there is built-in self diagnostics, which can be read through the A/C display. All Data will show you how to do that.

You also have a cabin air filter that may be badly plugged up - how is the airflow volume?

There is no water control valve in that car, they simply isolate the heater core airflow with a door. There are a several sensors in the system, plus the servo motors.

B.

Edited to add:

There is also a TSB for the 2002~2005 Altima regarding a debris screen for the fresh air intake > NTB04-135, issued 11/11/2004
Apparently they di not provide any screen at all in the fresh air path. Do you park under a tree?


-------------------------
"Among the many misdeeds of the British rule in India, history will look upon the act of depriving a whole nation of arms, as the blackest."
~ Mahatma Gandhi, Gandhi, An Autobiography, M. K. Gandhi, page 446.

Edited: Wed July 09, 2008 at 12:48 PM by bohica2xo

ktod101 on Wed July 09, 2008 4:45 PM User is offline

ktod101 on Wed July 09, 2008 4:49 PM User is offline

regarding the debris screen for the fresh air intake would this have any effect on the ac. i do park under a tree i front of my house everyday. where is the debris screen located? i am going to take the dash apart and see if i can mess with the duct work.
thanks for all the help

ktod101 on Wed July 09, 2008 8:03 PM User is offline

ok i changed the filter,( the filter was very dirty and a piece of the filter was missing. probably worn out by the fan) the blower works a lot better. when i first started the car it was around 65 degrees. i added a little refrigerant and the temperature dropped to 50 degrees while the car is park, and stayed cold. while driving the car the temperature went up to around 100+ degrees.
still not working

mk378 on Wed July 09, 2008 8:20 PM User is offline

See if the compressor is still running and the suction line is cold when it blows hot, if so you're defintely reheating. Sounds like with all the electronics, it could be a rather complicated repair. For now you could disable the heater by disconnecting the coolant hoses or splicing a valve into one of the hoses. Then deal with it in the fall.

Since you have no pre-screen, leaves and stuff will have gone thru the hole in the filter, become mulched up by the fan, and lodged in your evaporator and heater cores, reducing air flow. Often a hole in the filter means that a mouse or two have moved into your ductwork as well.

Back to Automotive Air Conditioning Forum

We've updated our forums!
Click here to visit the new forum

Archive Home

Copyright © 2016 Arizona Mobile Air Inc.