I just finished replacing my compressor, high pressure hose, and drier. I did it in about 8 hours. Now that I know what to do, it should only take about 2 hours if everything goes right. I felt that my AC system never really ran correctly. My car never really got that cold, and something made a noise when my compressor clutch would engage. I took it to the dealer 3 times, and each time they said it was a loose belt, but how long is that excuse going to work? I guess it worked all the way until my compressor seal failed! Those jerks conned me just long enough to get out of the warranty. Anyhow, in 2005, I had to add about 2 cans of R134/year. Then in 2006 it went to about 3 cans, and in 2007, it got to one can a day! I put leak stop in, but that did nothing. I used green UV dye, and noticed a huge puddle of green on the cover below the oil filter, and a green coat on everything near the compressor pulley. There was an even coat on the HP hose (compressor outlet), so I thought it might be leaking at the HP hose also. Since I was going to break the system, I decided to replace the HP hose, compressor, and drier. When I had R134a in the system my car would get cold, so I didn't want to mess with the expansion valve since that probably worked.
I priced out the replacement parts and I got a remanufactured compressor for $294 (ac autoparts warehouse with clutch assy), drier $54 (AC part place in Merritt Island, FL), and HP hose $93 (dealer). I read some articles that said O-rings may not have to be replaced, but I bought the entire kit for $10 anyhow just in case (I really didn't need any, but I replaced some anyhow). The dealer compressor was $591, which was a little more than I wanted to pay.
I did a lot of research online and at the Hyundai website to obtain drawings and removal tips. They also gave info on amount of oil to add. In general, the info was pretty good, but not great. There were good directions for working with the power steering pulley/belt, but not the AC compressor belt. They showed the jacking bolt to turn in order to loosen and tighten the belt, but they neglected to show which nut was the locking nut. It is the one on the tension pulley itself! Even after loosening it, I moved the jacking bolt in both the tighten and loosen directions without changing the tension on the pulley! This was my first roadblock. Finally, after an hour, I guess I loosened it up enough for it to move it. My next problem was to remove the drier. I looked simple, but it was located between the car grill and condensor WITH NO ROOM! I could barely get a wrench on the nuts! What a joke this layout was. To add to my misery, the nuts were rusted and would not come off. After using PB blaster and fooling with it for 1.5 hours, it came off. I had to hold the compression nut with a wrench and turn the entire drier with vise grips. After 1/4 turn, I had to take the wrench off, rotate the drier back 1/4 turn, and do the process again. What a pain. My next road block was the HP hose. The part came with an alignment pin. Which seemed good, but the manifold the hose goes into already had a pin in it! So, I had two pins and no holes. I tried to remove one of the pins, but they must have had a very tight fit because neither would come out. So, I ended up using a Dremmel cutting tool to cut each off, and then used a Dremmel sanding tool to make the seating surfaces flat. What a chore. I had to be careful not to nick either surface. My next road block was getting the compressor out of the engine compartment. I was able to remove the bolts that held the compressor to the engine (one bolt is longer than the rest so be careful), but then the compressor had too big of a foot print to remove either out the bottom of the car or out through the hood! I eventually ended up removing two bolts from the right side of the radiator and pulling it just far enough forward to slide the compressor out the top. The next trick was to reassemble everything. It wasn't too bad except for the drier. Again, no access made it difficult. I can't believe I was able to get the bottom fitting on and sealed. I only got about 3 turns on the fitting, but it seemed to have worked. I pulled a vacuum, charged 2 cans or R134, and now the system works like a champ, even better than before. General gripes would be that I had to work from the bottom of the car with only jack stands (not much room), you have to remove the right front tire and remove a splash guard (bolts are not very accessible for the splash guard), and that the system was corroded. I was fortunate that AutoZone lent me HP/LP manifold gages and also a vacuum pump. I couldn't have done the job without their help.