Charging 2001 Eldorado AC?

[Bill Caddyshack]

On my 2001 Eldorado, charging my ac. I am new at doing this.

My gauges should read, with ambient temperature at 85 degrees or so, should be getting about 40-45 low (suction side) and 170-180 (high side), according to the book.

Getting "Low freon AC off". So, I put the gauge on the car and get 20 on suction and about 25 on high side. I clear the codes on the OBD and the freon starts flowing in nicely.

The low gauge goes to about 70. 
The high side does not move above 25.

I think everything is hooked up right.

Low, suction, (blue hose on gauge) is the larger line that gets cold.
The High (red gauge hose) is the small line that gets hot.

Codes keep coming back with low freon and ac shuts off.

Any ideas?

[Commodore]

First see if this video can find your problem.

http://www.youtube.com/watch?v=UW1GDiOa0kE

[TJ Hopland]

Where are the ports on that car?   Like right on the compressor?  Or is the low somewhere else?  Can you see where the pressure sensors are?  Or can't you really tell since its all so jam packed?   If the low port is not right at the compressor I would think there has to be a blockage somewhere not letting the 'low' get to the compressor.  I suppose it could be a issue with the early stages of the compressor too not letting it in.

[Scot Minesinger]

Your reading on the gauges seems to indicate a blockage and the Freon is going in reaching 70psig (higher than it should be), and not going out (high side 25psig, way lower than it should be).  Watch that video.  Just to confirm you should be adding R134 when compressor is operating and clutch is engaged.  You may have a simple error that we all suffered through when we first started doing this.  You will win.

Good luck,

Scot

[Gene Beaird]

The ports on most R134 systems are not swappable.  That is, the low side will only hook to the low side port (the connector is physically larger).  That is if you're using the factory quick-connect fittings. 

I have had issues with some of the newer gauges working properly.  Some have a really cheap little brass depressor that some systems don't even use, which keeps the freon from flowing.  Verify you aren't enjoying this issue.  Otherwise, as others have said, you may have some blockage, usually in the orifice tube, since the screen is pretty fine there.  I would verify your compressor is running, though.  If you're pressure is too low, the low pressure switch may not allow the compressor clutch to engage, which might require unplugging the switch, and jumping across the terminals in the connector with a simple wire until you get enough pressure to run the compressor normally. 

[TJ Hopland]

Thats why I was asking where the ports are located on this car,  knowing the overall layout of the system on this car may give us an idea where the blockage is.   It would be nice if they would make em all the same but they don't.   Many times you can't even find the darn things anymore so he may not be able to tell what the system layout is without tearing the whole car apart.   I worked on one car recently where you had to remove the front tire and inner fender to get to the low port.

[76eldo]

I remember in the Allante forums that there was something you had to do on the DIC to get the air to engage after filling it.

Brian

[Dave Shepherd]

The system should be purged and  using a charging station pulled down to see if it holds vacuum, then using the charging station fill the system as the held vacuum, if it leak free, will pull the charge in. Question is where the the freon go to begin with?  Really should be professionally leak tested.

[Bill Caddyshack]

Internet was down for me couldn't answer sooner.  I made a bad read on my gauges. The high and low sides are the same number, about 70 psi. Yes, the high pressure gauge can only work on the high pressure fitting same with the low.

I'll take a picture of the layout and post it tomorrow. Thanks for all the suggestions. Good night for now.

[TJ Hopland]

High and low were the same with the compressor running?       What was the pressure when compressor not running?

[Bill Caddyshack]

High and low were the same with the compressor running?       What was the pressure when compressor not running?

Not running, 40 psi on the low side a next to zero on the high side.

[TJ Hopland]

So compressor running is 70 and 70?  And not running is 40 low and 0 high?

That's not right.   After a few minutes not running both sides should be equal.   You have something blocked up somewhere.

[Scot Minesinger]

Yes, you may not have the gauges set up right, the hi/low side connections are some mistake typical of a talented person starting to learn how to use these tools.

Depending on the gauge set connections you have to turn them clockwise to open (as opposed to counterclockwise), some press on depressing valve and are automatically open, then there are the gauge set valves to get right so one of the gauges is not bleeding through the middle hose, and etc. 

Once all those things are sound, understood, and set up correctly you can probably figure this out without us.  If you have a vacuum pump that can get your gauges set up easy.  Attach hi gauge to vac. pump should read -14.7 psig, then do same for low and reading should be same, then you know gauges read what is attached to hose.  Then attach gauge to hi side and vac pump to low side, should get a vacuum reading and that means no blockage, ports are open and all is good.  This can start you off.  If you don't have a vacuum pump, buy one, as it will pay for itself almost on this charge and easily be worth it if you to use it again.   

[TJ Hopland]

I didn't think of the gauges being set up wrong.  That would almost make the most sense as to why those readings are the way they are.   With most of the system layouts I have seen I don't quite know how you would end up with those readings.

I now remember when I got my set that I had to assemble it.   Mine was a mid to high priced set so everything is color coded so harder to mess up but I do remember when I was shopping there were some that were not as well coded so you could attach the wrong size fittings to the wrong gauges.    Most seemed to have a pretty clearly laid out valve system but I suppose there could be some that are not that clear there either.

[Bill Caddyshack]

I love Scot's statement,  "mistake typical of a talented person starting to learn how to use these tools."

I do feel like there is something right in front of me that is off, however it may be something in the Cadillac's marvelous electronic system.

Ok, here are the pictures.

[Scot Minesinger]

It is unlikely to be something electronic on the Cadillac, but it could be, check out the shop manual for charging instruction.  You never know, there may be an electrical circuit that needs to be unplugged??

It is hard to tell from the pictures, because we don't know position of valves and etc.

It may be time to get a friend in the local CLC, other car club, friend who is a mechanic, or etc.  to stop by and lend some knowledge.

[Bill Caddyshack]

I still get "Low Refrigerant - AC off" I have bled the extra freon into a tank and dropped the low pressure to 20psi, then added 134a through the yellow hose and see it go through the sight window. The Low pressure goes back up and the High Pressure (all valves open) stays even in psi with the Low pressure.

I guess I need to find someone to look at it. Most shops, other than dealers don't have familiarity with the Northstar engine and components.

I do need to get a manual. I have a shop manual downloaded from an eBay seller, but there is something wrong with it. Does not display and keeps asking for a password. Wish I could find a manual in pdf format like I have for my 1958, 1956 and 1959.

There is something about the gauges reading the same pressure that indicates a fault. The first video posted on this thread answered it, but I have  severe hearing loss and could not understand what the guy is saying and the captions when enabled are very weird and of no help.

May have to take it to a dealer- last resort!

[Scot Minesinger]

Shop manual, experienced a/c mechanic friend, then dealer

[TJ Hopland]

So you have been able to get the compressor to run or not?  I suppose on that car its buried down low so its hard to see?

[Bill Caddyshack]

So you have been able to get the compressor to run or not?  I suppose on that car its buried down low so its hard to see?

The compressor runs fine. I just clear the codes that say the system has low freon and it kicks in and sucks freon from the can.

Best price i can find on a manual is, $280

http://www.ebay.com/itm/2001-Cadillac-ELDORADO-Service-Repair-Shop-Manual-Set-FACTORY-OEM-2001-BOOKS-NEW-/160891596305?pt=Motors_Manuals_Literature&hash=item2575e2ee11&vxp=mtr