How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site.
    Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask Dan Your Own Question
Dan, ASE Certified Technician
Category: Nissan
Satisfied Customers: 1080
Experience:  Dealer Auto Technician
Type Your Nissan Question Here...
Dan is online now
A new question is answered every 9 seconds

I have a 2000 Nissan Altima GXE 2.4L with an a/c problem.

Customer Question

I have a 2000 Nissan Altima GXE 2.4L with an a/c problem. The car will cool fine (vent temperature 50⁰F; ambient temperature 85⁰F) at 750 rpms to about 1200 rpms (the clutch will not cycle). But as soon as I get the rpms above 1200-1500 the compressor will cycle on and off about every 12-15 seconds. My pressures at 750 rpms suction side is 29 psi, high side is around 175-180 psi (ambient temperature 85⁰F). But when I increase the rpms above 1500 the suction side drops to 15 psi, the high side goes to about 225. I was told that the expansion valve is probably stuck open. So when I went to replace the expansion valve I noticed there was oil on the evaporator coil – probably from a leak. So I replaced the evaporator coil, expansion valve, receiver/dryer and the high/low pressure switch/fan, along with a thermal amp sensor that measures the air temperatures that are coming from the evaporator coil and I also replaced the a/c clutch relay. It was vacuumed down and recharged with 1.5 lbs of 134A. This did not fix the problem. I did some more research and people are saying that the split condensers can also cause this problem if they are clogged. So I purchased a new condenser, broke the system down, cleaned all the lines and made sure they were clear, reassembled, vacuumed down and charged the system with 134A with no change. Would too much oil in the system cause this problem? Is there anything else it could be?
Submitted: 4 months ago.
Category: Nissan
Expert:  peterpete190 replied 4 months ago.

Hi my name is ***** ***** I will be happy to assist with this today.In some cases I may need more info to assist better.I apologize for any delay.

If there is to much oil in the system this causes issues with the compressor operating properly with ac pressures as well as causes a restriction or flow issue in the ac accumulator.If you can I would evac the system again which should draw out most of the oil then recharge without oil to see if this resolves the fault here.You will still have oil in the accumulator as well as compressor when you evac so this wont harm the system.

If this does not resolve the fault the accumulator may need replaced.

If more help is needed, use the reply tab to continue our conversation. If no further assistance is needed, kindly rate my service.You can rate at any time and we can continue to work on your question as this will not close out your question.Keep in mind in some cases it can be difficult to fully diagnose or help repair your vehicle without seeing it and I work on delivering the best possible answer from what I see to work with.

Thanks Pete

Customer: replied 4 months ago.
I did install a new accumulator I just called it a receiver/dryer. I will evac the system and recharge. I'll let you know the results later today.
Thanks Mark
Expert:  peterpete190 replied 4 months ago.

O.k.,sounds good.Let me know how this turns out here when your ready.

Thanks Pete

Customer: replied 4 months ago.
Ok I’m back…..My wife had a medical issue last Friday and I work weekends 12 hour shifts. I decided to break the whole system down again. I drained all components of oil including the compressor. The combined oil collected was 6 ounces and it was clean (no trash from compressor). I added PAG-100 to compressor and to all components (6 ¼ ounces total). Put system back together. Vacuumed for one hour and waited overnight. System held 29 inches with no loss. Recharged with R134A using 1.6 lbs. The Ambient temp 2” in front of condenser is 95F. Windows are open, a/c is on max and recirculate, fan is on high.
750 RPM Low 30 High(###) ###-####RPM Low 20 High(###) ###-####RPM Low 18 High 275
It’s still cycling on and off. What is causing this?
Expert:  peterpete190 replied 4 months ago.

This is a tough one for me to answer myself here but others here may be able to help more.

I will open your question up for others here to see if someone else can assist further on this as there may be others here that may have more info on what to check or do with this issue.I hope you can get this resolved with ease.No need to reply to my last post here unless it is a last resort as it will keep your question locked to me and others will not be able to view it.If you feel you want to continue to work with me on this feel free to reply at any time but keep in mind in some cases it can be difficult to fully diagnose or help repair this without seeing your vehicle.

Thanks Pete

Expert:  Dan replied 4 months ago.

Is the AC condenser Cooling fan coming on?

Customer: replied 4 months ago.
as soon as the a/c button is pushed on the fan comes on.
Expert:  Dan replied 4 months ago.

Your low pressure side is too low. You said you already replaced the expansion valve, which yes could cause this problem.

Replace the compressor.

Expert:  Dan replied 4 months ago.

On a fully charged system, insufficient low-side pressure is normally the result of a restriction. A clogged orifice tube is a common cause of such problems. The high-side pressure may be elevated as the compressor attempts to force the refrigerant past the obstruction. This will quickly starve oil flow to the compressor and cause a catastrophic failure.

With any restriction, the source of the debris must also be considered.

Expert:  Dan replied 4 months ago.

How does the condenser look?

Customer: replied 3 months ago.
The condenser looked clean, but I replaced it just in case it was clogged internally. I replaced the expansion valve twice - thinking that maybe the new valve that I had put on was bad.
Expert:  Dan replied 3 months ago.

Could also be a compressor problem.