tnj9

So recently replaced dead AC compressor and interior blower motor in my 03 GLE with 163k miles. Interior cabin filter cleaned first time in 12 years, never really knew it was there. Guy who put in compressor put in 2 cans of r134 after evacuating system and installing new compressor. But new blower and fan amplifier didnt come yet and I was installing that myself so he said not to run it. I put the blower in and it worked fine, except when AC was on full blast at idle it blew lukewarm, engaged for a second or a few at a time along with rad fans at idle, and caused change in rpms. Had an old AC pro gauge with trigger lying around garage and hooked it up to low side and in 40 deg weather was reading 45-50 psi dropping about 5 when compressor engaged. Frusturated, I thought of a solution, squeezed the trigger to bleed out a little r134 at a time (i know, probably not a good idea), doing so however, as pressure decreased the frequency of clutch engaging increased, so I continued until it reached a state of equilibrium at 20psi with the compresser and fans now running as they should with no fluctuations of pressure or changes in idle rpm. I realize this wasnt the best idea but could it have solved my problem? Or will something else arise in what I feel like is a constant struggle and a love hate relationship with my max which is very well maintained overall.

tnj9

Bump, really need some advise from someone more experienced than myself in heating/cooling system. Ran it again today and again, ran fine but still cautious.

q.man06

iTrader: (2)

If the compressor is cycling on and off that usually means the pressure is too low on the low pressure side. As the compressor pressurizes the high side the low side pressure naturally goes down. If you hook up a manifold set you can clearly see with the ac off the high and low sides reach an equilibrium.

Check the sticker under the hood and it should give you the quantity of freon required in lbs. If he put in two 12oz cans that's 1.5lbs which sounds low to me. I don't recall the spec right off hand but i'd be willing to be it's around 2lbs. Being half a pound low will cause the issue you were having to some effect. Estimate how many ounces you added to the system and ask the guy how large the cans were that he put in. You don't want an AC system under or overcharged.


-- Just re-read and it looks like you removed freon from the system? Maybe it was overcharged. I believe it can act the same under too high of pressures too. Best to verify how much was put in originally and compare with the system capacity.

tnj9

Correct, I believe it was over charged given low side 50 psi in 40 deg weather and trying to drop when compressor kicked on but switch kicked it off to prevent damage. Im wondering if it is where it should be around 20 psi in 30-40 deg weather on low side holding steady with clutch and compressor engaged and ac on max blowing cold in cabin. Previously was blowing warm and cycling and causing idle fluctuations that affected driving when new compressor/clutch kicked on/off. I just hope I didnt introduce any moisture by bleeding this way and that the system is safe to use. I feel like I may have been lucky and got to the sweet spot with the low side gauge only but its hard to tell. I believe it was filled with 2 full 14oz cans.

Child_uv_KoRn

iTrader: (7)

I hope oil was added.

tnj9

Yes 6oz PAG 46 with UV detection

Child_uv_KoRn

iTrader: (7)

Just checking since someone else did it

I really trust people Lol

tnj9

Its a friend of mines dad whos a mechanic and I was assisting and watching the install. Was a PITA because I didnt want to buy a new OEM one specifically for the 03 Max because of $$ constraints so I bought the "remanufactured 03 Maxima Altima 3.5 V6 AC compressor" from a reputable seller on ebay. Turns out hoses were 90 deg off so probably off an Altima or different vehicle all together, no friggin stamp or number on the thing. Many hoses had to be tediously bent and manipulated to get it to work but it did. I dont think a shop would have done this lol. But, it does work and blows very friggin cold hence positive seller rating?

DennisMik

iTrader: (2)

According to the service manual, the 2003 Maxima a/c takes 1.1 pounds of refrigerant.

tnj9

Right, I thought I saw somewhere online that it was 18oz which is probably your 1.1lbs given 1=16 meaning 2 * 14 = 28 = overfilled by approx 10oz which explains nearly 45-50psi low side to 40 with clutch engaged causing problems and venting to around 20-22 allowed it to work. The system was nearly 2x overfilled.

tnj9

Ok so after a month of the system working fine it decided to completely stop working today. Yesterday I had completely cold air blowing and it was just slightly cooler out than today. Today I go to work at 12 when it's already 80 and probably 100+ in the interior of the car and it blows lukewarm/hot air on any cold setting auto or manual any fan speed. Ugh. Got home just now and popped the hood with the system on max auto AC at idle and the rad fans are constantly on (not cycling like the problem I had before) and the compressor is also constantly on. Now I'm stumped. Took the cheap low side autozone gauge I have in my garage and hooked it up to the low side with the system running and it's reading around 5psi, what? Refrigerant levels are not low and I recently checked the system for leaks with a blacklight when I had the car on ramps. Shut the climate control off and the gauge went up to 45psi, apparently perfect pressure for the ambient temperature (~80 deg). I have absolutely no idea what is going on here. Any help is GREATLY appreciated, I am low on funds now for more friggin car repairs after that recent valve cover job and cant afford to take it to an AC specialist to pay a ridiculous price for an evaluation let alone inflated cost for parts/labor.