bwguardian Posted October 3, 2023 Report Share Posted October 3, 2023 (edited) We bought back our middle daughters car...long story...which is a 2008 Ford Edge Limited and have had it up and running since the middle of the summer. The a/c has been cooling fine at 45*-48* vent temperature depending on outside air temperatures...it's been really hot. Sunday we drove the car and everything seemed okay on the short trip to and from church. So a couple hours later we get in the car to go get our youngest daughter and immediately notice the a/c blowing warm air. I cycle the a/c system on/off and my wife noticed in the beginning there was a short burst of cold air before going warm. When we got back home I noticed the compressor clutch was engaged when the a/c was on but the refrigerant line coming off the compressor was not cold. I also checked it the next morning after sitting all night and that's when the compressor clutch would not engage when turned on. I hook up Forscan to check DTC codes and there's nothing related to the a/c system. I also did the KOEO self test and the fans powered up, then the compressor clutch engaged. I hook up a set of gauges and the high and low side were just above 0 with engine off. So I jump the compressor clutch relay while the engine is running and get a reading of -20 on the low side and +20 on the high side, but I did not let it run long given the compressor could be damaged due to lack of lubrication. The difference in pressures when running is telling me the system is still somewhat closed, but maybe it's just showing the compressor is still doing it's job and able to pump. Either way I need to look for a leak. I looked at another thread with a similar issue where a blow off valve was mentioned...assuming that would happen if there was a blockage...but I didn't hear the hissing and/or pop if that valve would of let refrigerant out. The fact the compressor clutch was still engaging when we returned home the second time, I'm thinking a slower leak. The op found a bad discharge line down by the compressor and I did notice some residue down there when looking to see if the clutch was engaging, so I'll start there when this rain lets up. Given I will more than likely have to suck the system back down and recharge it, I may as well take a look at the orifice tube for debris, but not sure where it's located in the system... Edited October 3, 2023 by bwguardian Quote Link to comment Share on other sites More sharing options...
Haz Posted October 3, 2023 Report Share Posted October 3, 2023 1 hour ago, bwguardian said: Either way I need to look for a leak. From the 2008 Edge Workshop Manual... Fluorescent Dye Detection NOTE: Ford Motor Company vehicles are produced with R-134a fluorescent dye installed in the refrigerant system from the factory. The location of leaks can be pinpointed by the bright yellow-green glow of the fluorescent dye under a UV lamp. Since more than one leak can exist, make sure to inspect each component, line and fitting in the refrigerant system for a leak. Good luck! 2 Quote Link to comment Share on other sites More sharing options...
bwguardian Posted May 27 Author Report Share Posted May 27 I've been taking a closer look into this given we are now into summer time heat. So I was able to vacuum the system down and hold about -26 on the low side and it holds long enough to tell me there's not a leak. I went ahead and put a can of 134a in and the compressor clutch engages right after I start the process. The system takes almost 2 cans so I wanted to see what would happen before topping it off. I drove it around and let it idle in the driveway for an hour with no issues so I added another small can that has refrigerant, o-ring conditioners, and some dye. Drove around again and the vent temperature was 48*. I had to go pick up our youngest daughter from school so made the trip and the car sat in the parking lot for an hour. I drive the car home and the vent temperature is only 70*. I put the gauges on it and decide to put another can in. It's now blowing 45* idling in the driveway. It needed gas so I take it around a long block drive and it's blowing 36* so I decided to go put some gas in it which is a couple miles away. I get to the station and there's a line so I wait. I see a free pump so I pull up put the car in park and leave it idling. When I do I noticed a mist cloud from the passenger side front. I fill the tank and get into the car where it's blowing warmer again. I get home and notice the green dye around the compressor down low. I'm thinking the compressor blow off valve is releasing refrigerant because of high pressure. When I had it idling in the driveway the gauges were reading 26 on the low side and 185 on the high side the first time with just the one can. When I added more it went to 30 on the low side and 225 on the high side. These numbers were taken while it was 90* outside. I'm thinking there is a restriction in the system that shows up once I take it for a drive. I'm leaning towards the compressor is obviously working, so I'll leave it alone for now. I've ordered an expansion valve and drier thinking this may be my problem. I'll investigate further when I get it apart unless anyone thinks differently. Since the expansion valve is on the firewall and I need to change the spark plugs anyway, it will help by pulling the intake plenum. Given the system will be open it just seems like good measure to replace the dryer and check if it's still intact...if not, it could also be my blockage problem. The only other culprit would be the pressure valve. I did read another thread relative to the compressor discharge hose separating causing the leak, but they never answered about the blow off valve... Quote Link to comment Share on other sites More sharing options...
garycrist Posted May 28 Report Share Posted May 28 @bwguardian These automobiles have a critical charge and just a little more and a top-off can have disastrous results. A little less is "way mo better" than too much. The old "Ford System Performance Test" (I enjoyed that in the summer in Kansas) was to run car @2500 RPM, Recirculate/Max, and fan on high center register. System %100 if air temp is 40 F. That would be about 28- 30 PSI. R-134 and R12 have about the same specs too as the pressures (temps) are about the same. From what you said above if you did not splatter the compressor (too much liquid) then the orifice is OK. 90 degree day high side was OK, low side less than 28 system will cut-off (temp is less than freezing liquid may return to compressor). Quote Link to comment Share on other sites More sharing options...
Cerberus Posted May 28 Report Share Posted May 28 I'd be using an ultraviolet lamp and glasses to track the leak down. no point in replacing what might be fine, at least not until you know what is the actual problem. obviously leaking, possible blow off valve dumping prematurely, but to e honest, i've never heard of that happening. probably a pin hole in the condenser, leaking shrader valve or seal failure at the compressor high side line 1 Quote Link to comment Share on other sites More sharing options...
bwguardian Posted June 12 Author Report Share Posted June 12 On 5/28/2024 at 4:03 PM, garycrist said: @bwguardian These automobiles have a critical charge and just a little more and a top-off can have disastrous results. A little less is "way mo better" than too much. The old "Ford System Performance Test" (I enjoyed that in the summer in Kansas) was to run car @2500 RPM, Recirculate/Max, and fan on high center register. System %100 if air temp is 40 F. That would be about 28- 30 PSI. R-134 and R12 have about the same specs too as the pressures (temps) are about the same. From what you said above if you did not splatter the compressor (too much liquid) then the orifice is OK. 90 degree day high side was OK, low side less than 28 system will cut-off (temp is less than freezing liquid may return to compressor). From what I can see the system holds 21 oz. and I only put in 12 oz., so it was less. The compressor works as it gets cold so maybe there's a restriction in the orifice causing refrigerant to blow out of the compressor. I took a look at it and I see the green dye on the bottom of the compressor. It could be blowing out of the front seal or what looks like a blow off valve. Is there a blow off valve on the bottom of the compressor near the oil filter? Quote Link to comment Share on other sites More sharing options...
bwguardian Posted June 12 Author Report Share Posted June 12 On 5/28/2024 at 6:09 PM, Cerberus said: I'd be using an ultraviolet lamp and glasses to track the leak down. no point in replacing what might be fine, at least not until you know what is the actual problem. obviously leaking, possible blow off valve dumping prematurely, but to e honest, i've never heard of that happening. probably a pin hole in the condenser, leaking shrader valve or seal failure at the compressor high side line I've narrowed it down in that I'm seeing green dye on the bottom area of the compressor. There appears to be a blow off valve on the bottom of the compressor, adjacent to the oil filter. It's either coming out of there, or the front seal of the compressor. I am thinking there may be a restriction...possibly the orifice...causing this. I may need to put some more refrigerant in it and monitor the pressures above idle... Quote Link to comment Share on other sites More sharing options...
Cerberus Posted June 12 Report Share Posted June 12 21 minutes ago, bwguardian said: I've narrowed it down in that I'm seeing green dye on the bottom area of the compressor. There appears to be a blow off valve on the bottom of the compressor, adjacent to the oil filter. It's either coming out of there, or the front seal of the compressor. I am thinking there may be a restriction...possibly the orifice...causing this. I may need to put some more refrigerant in it and monitor the pressures above idle... if you end up seeing some extreme pressures with standard or low refrigerant charge level, you may have a ruptured desiccant pack in the receiver / dryer.. Might be a long shot, but its possible, and it would explain leakage out the blow off. If its not leaking from the blow off, its most likely leaking from the high side line seal at the compressor. That would actually be good news. Point of interest, the vacuum test, while useful, can be misleading because sometimes seals really only seal well in one direction (pressure) I've had systems not hold vacuum well, but hold their charge just fine. The opposite can also be true. Quote Link to comment Share on other sites More sharing options...
garycrist Posted June 13 Report Share Posted June 13 What kind of high side and low side pressures are you seeing at 1500-2500 RPM and your outside temp. BTW don't let the high side get above 275 PSI without spraying the condenser with water if the fans don't pull enough heat from the condenser. If the high side sky-rockets and the low goes negative then yes you have a blockage. Then it's compressor, receiver/dryer and orifice valve. (have puller handy, just in case). Look for metal or desiccant in the orifice valve. Flush the system if metal found too. Quote Link to comment Share on other sites More sharing options...
bwguardian Posted June 13 Author Report Share Posted June 13 14 hours ago, Cerberus said: if you end up seeing some extreme pressures with standard or low refrigerant charge level, you may have a ruptured desiccant pack in the receiver / dryer.. Might be a long shot, but its possible, and it would explain leakage out the blow off. If its not leaking from the blow off, its most likely leaking from the high side line seal at the compressor. That would actually be good news. Point of interest, the vacuum test, while useful, can be misleading because sometimes seals really only seal well in one direction (pressure) I've had systems not hold vacuum well, but hold their charge just fine. The opposite can also be true. Where is the high side line? It looks like on top, but is it closer to the back (where the oil filter is) or to the front (where the clutch/pulley is)? Looks like I may need to pull the compressor. I've looked at it and depending on the slack in the lines doesn't look too bad, but I've also seen where that nut on the stud becomes an issue running into the frame... Quote Link to comment Share on other sites More sharing options...
Cerberus Posted June 13 Report Share Posted June 13 1 hour ago, bwguardian said: Where is the high side line? It looks like on top, but is it closer to the back (where the oil filter is) or to the front (where the clutch/pulley is)? Looks like I may need to pull the compressor. I've looked at it and depending on the slack in the lines doesn't look too bad, but I've also seen where that nut on the stud becomes an issue running into the frame... I dont know for your vehicle off hand, I'd have to figure it out from looking. It will be the skinnier of the two, and will flow to the condenser Quote Link to comment Share on other sites More sharing options...
bwguardian Posted August 12 Author Report Share Posted August 12 I'm just now getting around to this. Saturday I installed the expansion valve and I was able to blow through the bottom high pressure hole where the spring is. The spring assembly was a bit black, but the adjacent internal aluminum body was all sparkling clean. Went ahead and changed the plugs, then rotated the coils since the intake was off. I still want to change the drier desiccant bag thinking this may hopefully be the issue. I've looked online and can't find a definitive answer about how to get at the cap cover for the filter and bag. I've searched for the Edge, MKX, and the Taurus which are all about the same. One showed the MKX having an access through the radiator holding bracket, but the Edge/Taurus seem to need the front bumper cover and brackets removed...possibly the whole condenser too...to be able to access and change the bag drier. Does anyone know how to accomplish this? Quote Link to comment Share on other sites More sharing options...
garycrist Posted August 12 Report Share Posted August 12 More fun for being cool. Quote Link to comment Share on other sites More sharing options...
bwguardian Posted August 13 Author Report Share Posted August 13 (edited) It looks like I can cut the bottom of the radiator/condenser support to be able and access the cap to get at the screen filter and desiccant bag...just have to be careful with it. Didn't take long at all to remove the front bumper cover, but it looks like removing the rest of the brackets, supports, hoses, wires, etc. will which is why I will try with the hole like the MKX has. ^^^...you can see the aluminum tube where the desiccant bag resides, but no way to get at the cap on the bottom. ^^^...I can make an access hole where my thumb is from the bottom... ^^^...it's just some webbing to get through on the left from the bottom... Edited August 13 by bwguardian Quote Link to comment Share on other sites More sharing options...
bwguardian Posted August 18 Author Report Share Posted August 18 I was able to cut the corner of the radiator/condenser support on the side a little instead of coming in through the bottom to get into the desiccant bag drier. I also found my problem after getting it buckled back up, vacuuming the a/c system, and adding a can of refrigerant back in. It was cooling down to 48* at idle sitting in the driveway and 43* revving it to 1,800 rpm in the driveway on a 90*+ day. The gauges showed 32 on the low side and 220 on the high side at idle and the low side dropped to around 20 while the high side crept up to 240 when revved back up still sitting in the driveway. Drove it around the neighborhood several miles with no issues and it would cool down to 40*. Came back home to grab something I had to deliver which I sold and headed to the meet up place. When I went to park in a spot I got a mist from under the car where the compressor is and the temperature came up to 70*. I got out and looked under there and it appears to be the front seal on the compressor that is leaking. I'll be ordering another one either today or tomorrow and get that changed out, vacuumed down, and re-charged to hopefully be done with this. I wanted to show folks how I was able to get at the condenser to change the drier bag without having to drain the coolant and removing the radiator for future reference... 1 Quote Link to comment Share on other sites More sharing options...
bwguardian Posted September 11 Author Report Share Posted September 11 (edited) I finally found the culprit and wanted to report back in case someone else ran into this predicament. When I first started this I thought it was the blow off valve, then I moved to the front seal of the compressor given the oily green dye in the area. It's just so tight up in there to be able to see good, not to mention getting the compressor in/out of there. I installed a new compressor and pulled a vacuum on the system...20 pump run, 20 minute off to see if holds pressure, 25 minute pump run again, then another 20 minute off to see if pressure drops. It held 26 lbs. of pressure fine, but I did notice at one point it fluctuated a bit momentarily with the pump on. I shot a can of refrigerant at it and almost immediately I saw oily green dye under the car once the low pressure side was 20 and high pressure was 50. Upon closer look, it appeared the discharge line was the culprit. I pulled it down again and it looks like the bracket which attaches the line...at the hard line where it transitions to the rubber hose crimp...to the lower stud mount, rubbed a hole in the line. I ordered a new line, which doesn't have that bracket by the way, and put it in place. Sucked the system back down again and it held a steady 26 lbs. I shot another can into it and it seemed to be good and was getting down to 45 degrees sitting at idle in the driveway showing 30 lbs. on the low side and 200 lbs. on the high side while it's 85 degrees outside. I drove it a little and it's getting down to about 40 degrees with only one can in there. I'm going to leave it be for now given our hot weather is mainly over, and will add the rest next year before we get into the hot summer again. I'm good with it since it now has a new expansion valve, desiccant element, compressor, discharge hose, and o-rings for the affected areas. On a side note, in between this scenario I installed an Atoto stereo head unit with a backup camera. It's a nice upgrade with navigation, touch screen, etc. I was able to keep the volume and scan buttons on the steering wheel. I also fixed the amplifier glitches so it wouldn't drop out and go to mono stereo...pulled the amp and heated the solder on the circuit board for better connection. Now I just need to turn off the TPMS dash light and message by disabling it through Forscan. I will get it inspected and registered tomorrow so our daughter can take her scheduled driving test this coming Monday. Edited September 11 by bwguardian Quote Link to comment Share on other sites More sharing options...
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