2002 QX4 A/C Problem -

[dollerprod]

Hello, I found this friendly, helpful site after coming across this epic thread which saved me over $500 and took 20 mins to do on my own to fix the A/C. Turns out this was a notorious problem with the I-QX4. nicoclub has bailed me out of trouble a couple of times now.

Anyway I am now having another issue with the A/C. This time it is blowing fine and all, but the air is not cold at all.

Someone has told me I should try to recharge the refrigerant, but my understanding is that that shouldn't really be needed unless there was another underlying problem. How can I determine whether it is a problem with the compressor or something else? I suppose I need to check for a leak/blockage but I am not so sure exactly how to go about that.

Again, the "volume of air" being blown is fine, but the air is not cold whatsoever... Could someone please advise me where to start to try and workup what the problem. Is there some type of diagnostic I could run from the A/C panel?

2002 Infiniti QX4. Thanks for any help!

[Towncivilian]

Have you changed the cabin air filter?

Try running the self-diagnosis described on page HA-43 of the factory service manual to help determine if there's anything wrong with the system.

[dollerprod]

Hi TownCivilian, thanks for coming in!

I'm 90% sure I replaced the air cabin filter when I had to change the fan control amp a while ago.

Here is a video since my phone was handy when I went through the diagnostics you pointed out. I don't think that the code displayed on the 2nd step (where it was flashing a "5" after the "2") is what we are looking for, but I'm having trouble making sense of it. Did I go through the process correctly?

Here is how it went down:
[youtube]http://www.youtube.com/watch?v=nrrkBVOxmaA[/youtube]

Looking forward to further advice! And, thank you!

[GRNMACHINE]

Not sure what you have already repaired/fixed. A leaking condensor will cause your symptom. The condensor is located in front of the radiator, a rock had put a hole in mine. Replaced the condensor, drier, o-rings, recharged a few years back. Was nice to have A/C working again for a few years. Back to your symptom again. Tried recharging, A/C was cold! Next day, warm air. Have a leak again, not sure if it condensor again or somewhere else. Not exactly sure how to diag this one. Hole in the condensor was easy to see, dont see anything obvious this time. IF its the compressor, wont be spending the money to fix... Meant to have it looked at during the strut recall, but slipped my mind.

[Towncivilian]

25 indicates a sunload sensor fault. However, this may be caused by not being in enough sunlight; the sensor may be working properly. If possible, point a lamp at the sunload sensor (the black circle next to the upper air vent) then try running self-diagnosis again.

[dollerprod]

GRNMACHINE:
Thanks for the post. I realize you were/are looking for help yourself but the post gave some idea/thoughts to think about nonetheless.. Most importantly: you mentioned something about a strut recall???? I was not aware of this. And it concerns me because I have always been disturbed by the way the car handles itself, especially at higher speeds (like on the interstate). It's very hard to explain, especially for me because as you can tell, I'm no mechanic, but it feels as if the car sort of "floats" - or like there is a pocket of air under the vehicle. It doesn't feel comfortable driving at high speeds. It feels like even subtle turns (like around bends, lane changes, or especially if I have to correct or do something unexpected because of traffic or something)- that I can't do anything but super minor adjustments or it feels like I might lose control. It scares me. And in fact about 3 years ago it started raining hard and just from going over an overpass and the change of asphalt to pavement "bump/lip" I actually spun out on the overpass bridge on I-95!!! I have been super alert and concerned since. But I thought I might just be being paranoid because of the incident I just described. I need to find out more info about the shocks/ struts or whatever else it may be.

TownCivilian:
Thanks again for coming back! Ok, so I did it again in the direct sun. No youtube video this time..
Step 2: after about 10 seconds displayed "20" (as it should, right?)
Step 3: after about 40 seconds displayed "30"
Step 4: scrolls through the different vents
Step 5: said "100°F", 106°F", "95°F" (display on ceiling read 80°F)

So yeah, I guess the sensor wasn't "in view" of the sunlight.... Does that help with diagnosing/ what I should do next at all? Thanks so much for your help! I'm dying to get this taken care of. It's still damn hot here in FL! And I have a 1 1/2 yr old; it's too hot for him. So, thanks for any tips to point me in the right direction!

[Towncivilian]

You should forget about the A/C for now and take a look at the strut housing corrosion recall thread. Has the vehicle always been in Florida? Mine has and it only has a tiny bit of surface rust.

[dollerprod]

ahhh man, this is just what I need right now ... Anyway, I have literally 2 mins right now so I am not able to read entirely through that thread. I have only read the first page where people were trying to determine if their vehicle was repairable, and if not what the buy back value would be. I love my truck and don't want to get rid of it. The book value is not even close to what it is worth "to me". But....

Is it possible that this is the cause of the handling issue I posted above? That this is related to when my truck spun out in the rain on the interstate?

Yes, it has always been registered in Florida, to the best of my knowledge. The original owner traded it in in Jacksonville (where I bought it) and to the best of my knowledge that is where it was purchased new. I'm not sure about that though.

Is this inspection/recall thing still "active"?

I really don't know what to do but hopefully I will have more time to read about it over this weekend. Any tips, further information about this I should know?

Thanks for helping me.

[Towncivilian]

Perhaps I should have mentioned to read the TSB about the recall rather than the thread, my apologies. You should be able to inspect for rust in the wheel wells following the pictures in the TSB. And yes, the recall is active for all vehicles that haven't been inspected or repaired yet. You were supposed to have received a notification letter in the mail about it, I'm wondering why you didn't.

If there is any strut corrosion and it is severe enough, it may have contributed to your highway spinout. Do you ever get excessive wobbling or swaying at higher speeds on the highway?

[dollerprod]

No I never received any letter in the mail about the recall. Plenty of sales materials, but no recall letter. Is it because I am in FL and FL is not listed on the TSB?

Should I just make contact with an Infiniti dealership? There isn't one very close to where I live, can I contact a Nissan dealership about it for an inspection?

[Towncivilian]

There is an inspection for all states and you should've still received a letter. I just have not found the other corresponding TSB for non-salt states; non-salt state vehicles do not receive a free undercoating. Everything else should be identical between the TSBs.

Yes, call your local Nissan dealer. They should be able to inspect it.

[dollerprod]

You're the man. Thanks for all of the info! You have saved me so much time, just by your responses.

I will start with the inspection at a local dealership and make the initial contact on Monday.

But back to the A/C... I'm guessing that there is not much to tell by the diagnostic ran from the A/C display panel? (results I posted above) I think it seems like it all checked out alright.... Anything else you can think that I should try? Before going to mechanic..

[Towncivilian]

You're welcome

Yes, it seems that everything checks out with the HVAC control system. Perhaps try finding a shop that does an inspection for free, they'd probably check high and low side pressures to see if there's a leak somewhere.

[dollerprod]

I took it to a local mechanic. He wasn't available to speak with after the inspection, he left the keys for me and put an estimate on my seat says "need compressor" and wrote $499 new (inc labor) or $250 used.

I actually took a video of the compressor at the same time I did the diagnostic on the panel the first time (when I posted the first video). You can see that it looks like it is coming on. right?

[youtube]http://www.youtube.com/watch?v=OQvqmQbxqe0[/youtube]

[dollerprod]

So I really just kind of out of the blue thought to come back and report what has happened with this issue. I don't want you loosing sleep out of curiosity over it. It kind of resolved itself. I didn't do anything but the temp if "acceptable" now.

It does, however, now makes this sort of "knocking" sound when the a/c is on. It's pretty obvious. I even turn off the a/c at drive through windows just to shut it up. But it blows cold so...

[Towncivilian]

Ah, sorry I've forgotten about this.

Can you provide a video of the noise? My A/C compressor is quite loud but it still works great to this day. It did need a low pressure A/C line replaced and Nissan performed the work so I'd assume they put in the proper amount of compressor oil & refrigerant. Their invoice even noted that the compressor is noisy but that is nothing to worry about.