ac problems

[mc01ta]

I am the original owner of my 2007 nissan pathfinder and I'm having ac problems . my ac is not blowing cold air I had 70,000 miles and never had ac serviced. any ideas on what I can do or what it would cost to have the serviced or recharged?

[disallow]

Standard answer is you should take it to a qualified AC tech.

Depending on your location, you may be able to get R134a refill canisters and the tool that includes a gauge. I've done this in the past, usually after winter. This stuff usually has a sealant of some sort in it that helps to expand seals and prevent further leaks.

However, I've also had a situation where one of the tubes carrying the refrigerant was leaking. In this case, the tube needs to be replaced and the system vacuumed and refilled once the leak is fixed.

Without having someone who has experience look at it, its a shot in the dark.

t

[CPLTECH]

Just like to add, should you be adding Freon, be aware that the compressor is designed to compress a gas NOT a liquid. Therefore hold the can upright, whereas upside down is the liquid part.

[Oly 22]

My old vehicle had the same issue. Low refrigerant is the most common cause of a vehicles AC not cooling well. I did not try to recharge the refrigerant myself but that is all that was needed in my case.

[smj999smj]

Freon should never need to be added unless there is a leak. R51's came with dye in the freon from the factory. I would start looking for the leak before I waste money on freon. If you have rear AC, the first place I'd check is the rear AC lines; that seems to be a common failure. Look for a greenish-colored oil.

[Oly 22]

I agree to check for a leak first, you can visually look for the green refrigerant or use a leak detector. I personally do not know anyone that has one though. The AC system is a closed loop system and can work for many years without issue. You may never have an issue. That being said, the coolant can leak over time, albeit very slowly and most likely from from the O rings along the system. Vehicles over 5 to 6 years old could loose enough of the coolant where the AC does not seem to work properly. As mentioned, that is what happened to me in about year 6. In newer vehicles, if the AC isn't working properly, it would most likely be a leak and would need to be fixed prior to recharge. So I agree and kind of disagree with SMJ. Look for leaks first but if you cannot find any thing, it maybe the refrigerant slowly leaking form the seals.

Freon isn't used anymore do to the effect on the Ozone, R134A coolant is used and has less of an impact on the Ozone.

Give a call to your local dealer or mechanic and ask a few questions.

SMJ

My Pathy has the rear controls for fan speed and temperature in the back of the centre console. I believe these only regulate the amount of cold air or heat that is available from the front controls. Would this be correct? If this would be the rear AC , where do the rear AC lines run?

[smj999smj]

Rear AC and engine coolant lines run along the right side of the vehicle, above the exhaust heat shields to the cooling/heating unit in the right/rear of the vehicle on those models with rear AC. Here's a link to what the piping looks like that goes to the rear cooling/heating unit.

http://www.nissanpartszone.com/Page_Pro ... ageID=6469

[disallow]

SMJ, I don't understand your comment on liquid vs gaseous R134a. The low side port is on the liquid side of the system (pre-evaporator) so injecting liquid here would be fine, actually required, right?

[deermjd]

The low pressure port is located between the evaporator and the compressor. So the refrigerant is a low pressure vapor at this a point. The refrigerant can be added to the systm as a liquid through the high pressure port when the engine is off. But dont try this at home unless you know what youre doing.

[mc01ta]

Thank you for all the replies, guess ill have to take it somewhere. The ac never really blew that cold since the day I drove it off the dealers lot. Most of my other card blew much colder sir. This is the old console ac setup, its a pathfinder s. Out of the four settings, only number 3&4 get any bit of air going, setting one is nothing and two a very light breeze. On the coldest setting it is pretty mild.

I've seen condensation coming of the ac lines on realoy hot days last year and didn't think of much. It will drip it off ibto a small puddle when I'm at a stop in realky humid days. Is this normal?

I don't see any leaks with the good popped open but haven't checked the rear lines as I don't have a lift

[CPLTECH]

To respond to the comment that a sealed unit should never require additional Freon…
It was either in class or on a tour of the Carrier/Bryant plant where it was stated that there is no “perfectly” sealed system. They ALL leak, some more than others.

A car A/C system has many more opportunities to leak than a home copper unit. There are seals inside the compressor that leak to the great outdoors, as do piping connections. Also the high & low port valves can leak hence be sure the caps are good & snug. Yes, some unscrupulous techs have been known to leave the caps on the home unit a little loose so you WILL put in a call sooner than latter. Valves leak. If missing, go to AutoZone, etc.

In fact, it’s as if it is the rite of Spring to add some each year. Altho I put some in last yr, seems as it is not cooling down like last yr. Gotta put in a partial can, I guess.

[mc01ta]

Is it normal to have a condensation drip from the ac line in the passenger side rear engine compartment?

[smj999smj]

Condensation on the lines is normal when the system is operating, especially in hot weather.