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

a/c blows warm at high rpm's

cpdbatty on Tue September 23, 2008 1:08 PM User is offlineView users profile

Year: 2000
Make: Nissan
Model: Sentra
Engine Size: 1.8
Refrigerant Type: R134
Ambient Temp: 85
Country of Origin: United States

Customer complained the a/c would shut off at high rpm's and at idle for about 10 seconds it would kick back on blowing cold. We changed the thermister, evaporater, expansion valve, and a/c clutch relay. We even went as far as spending $700 replacing the ECM, and It is still not working. Please help!!!

mk378 on Tue September 23, 2008 2:30 PM User is offline

What are the refrigerant pressures as it goes through these cycles? Do the condenser fan(s) all work? When the compressor is not engaged though it should be, is the clutch getting power or not?

cpdbatty on Tue September 23, 2008 3:21 PM User is offlineView users profile

PRESSURES ARE NORMAL 210 HIGH SIDE LOW ABOUT 30, FANS WORK WHEN THEY SUPPOSE TO, A/C CLUTCH GETTING POWER.

mk378 on Tue September 23, 2008 3:42 PM User is offline

If the clutch is powered but it won't pull in, that means either the coil is open or the air gap is too wide.

cpdbatty on Tue September 23, 2008 5:59 PM User is offlineView users profile

But would that make it run cold at idle and turn off at high rpm?

mk378 on Tue September 23, 2008 6:24 PM User is offline

Once the system has normally cycled the compressor off once, it may be balky at coming back on when it should.

If you have the car powering up the clutch wire but the clutch is not engaging, the clutch is not working.

iceman2555 on Tue September 23, 2008 7:38 PM User is offlineView users profile

If not mistaken, the compressor on this vehicle has a temp/pressure cut out switch located on the compressor body. It is quite possible that at elevated rpm the pressure/temp of the refrigerant exceeds the specs for this switch. Insure that the system if totally charged and then check the inlet/outlet temps of the condenser...at idle...and at elevated RPM. An excessive temp drop indicates a restricted condenser. High and low side pressures are not always indicative of a possible condenser restriction. A test of the compressor outlet is sometimes all that is necessary to determine if this is indeed the problem.
Good luck!!!


-------------------------
The strongest reason for the people to retain the right to keep and bear arms is, as a last resort, to protect themselves against tyranny in government.
Thomas Jefferson



Edited: Tue September 23, 2008 at 7:38 PM by iceman2555

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.