AGrayson84
Active Member
Hi everyone, I bought a 2006 Navigator a little over a year ago, and when summer came around I noticed the A/C system performed poorly, especially while at a stop. If I drove down the highway without stopping for 35+ minutes, with the A/C on full blast (coolest temp setting on front and rear A/C systems, fastest blower speeds, recirc mode) I could eventually see 45 degrees coming out of the dash vents on an 80-some degree day. As soon as I'd slow down to 15 MPH or less, I could watch the outlet temp start increasing. Not rapidly, but after 6-10 minutes of having slowed down, I could see a 10 degree increase in temperature.
I'm going to cut out a lot of stuff that I did to the A/C system since last summer, because I replaced a bunch of parts and had no better luck. Cutting to last month, I have replaced the following with brand new Motorcraft parts:
Compressor, condenser, filter/drier, muffler, both expansion valves, both evaporators, all o-rings, fan clutch and fan blade assembly, heater valve, both front blend door actuators, rear blend door actuator.
Literally all lines under the hood were new. The only thing I have not replaced in this entire endeavor is the set of lines (suction and discharge), but they have been thoroughly flushed and dried with dry air. No debris or anything whatsoever was found in those lines except clean PAG oil. All new parts were then installed, 14 oz of PAG oil added to the compressor, 1 hour vacuum was done using a 6 CFM vacuum pump, after 30 minutes there was no vacuum loss and then system was then filled with a Snap-On A/C machine. 3.6 lbs of R134A was added. Everything has been done 100% to the book, twice now. But the A/C system continues to refuse to cool below 45 degrees on the highway, and continues to perform poorly for an extended time while driving down the highway.
I even went to the length of adding two, high-velocity, 12" electric puller fans directly attached to the back side of the condenser, thinking the condenser was getting not cooling well enough. It has helped bring the high side pressures down some, but has not offered a noticeable/worthy drop in outlet temperature.
My family owned a '98 Expedition from 2000 thru 2013. Never once serviced the A/C since new, and it never struggled to cool at idle, and blew 39-40 degrees out the vents without effort. This Navigator continues to take forever to cool no matter what I have tried.
Last week, we had a 98 degree day here in Maryland. I had a nice Covercraft windshield shade secured behind the windshield (these keep out a bit of heat compared to flimsy things you get at Walmart or the parts store), and my front windows are tinted to match the rear windows. So though it was hot outside, it wasn't exactly baking inside the car. I fired it up and let both A/C systems run full blast for 15 minutes. Got in the car and the outlet temp was 71 degrees. The car was still pretty warm on the inside, as 71 degrees coming out the vents doesn't cool as well as one might think in the hot sun. I drove the car for about 4 minutes to make it to the highway, and before hitting stop-and-go traffic, the outlet temp had gotten down to 63 degrees. Still not very cool, but did better now that I was moving. After about 8 minutes of being stuck moving from 0 to 10 MPH, the temp increased to 73 out the vents. A full 45-50 minutes after I started the engine, with the A/C systems STILL at full-blast, I was still crawling in traffic with only a 71-74 degree outlet temp. The car was still pretty warm.
Once I finally was able to pick up speed down the highway for a about 15 minutes I had gotten down to around 52 degrees outlet temp. This system is just struggling for some reason. I've owned 8 Fords since 2004, and not one of them has ever had a problem achieving 40 degrees or less out of the vents, especially when moving. Sitting still, I think 42 has been the warmest outlet temperature I've seen on any of my past Fords on a hot day. This one won't possibly below 70 sitting still on a hot day.
Even in inside my buddy's shop that was 72 degrees ambient temperature.... when we filled the A/C system to the 3.6 lbs, it still wouldn't get lower than low 50's coming out of the vents. We've clamped off both ends of the heater core and nothing improves. The rear system blows just about the same temperature as the front.... so it's not isolated to just one of the two systems.
What gives??? Nothing adds up here. The compressor isn't short-cycling, and nothing else seems to be acting up. When driving down the road on Sunday afternoon, it was 84 degrees out and I routed my R134A manifold gauge set thru the passenger's side window so my friend could monitor the pressures while driving. Low side was 25 PSI and high side was 196 PSI, and this was after 40 minutes of the A/C system running at full-blast.
Anyone with any solid suggestions would be really highly appreciated! At this point I have given up on it, but then every hot day while I sit in the car nearly sweating reminds me that I can't allow myself to have spent all of this time and money on parts and still be dealing with a hot cabin.
-Andrew
I'm going to cut out a lot of stuff that I did to the A/C system since last summer, because I replaced a bunch of parts and had no better luck. Cutting to last month, I have replaced the following with brand new Motorcraft parts:
Compressor, condenser, filter/drier, muffler, both expansion valves, both evaporators, all o-rings, fan clutch and fan blade assembly, heater valve, both front blend door actuators, rear blend door actuator.
Literally all lines under the hood were new. The only thing I have not replaced in this entire endeavor is the set of lines (suction and discharge), but they have been thoroughly flushed and dried with dry air. No debris or anything whatsoever was found in those lines except clean PAG oil. All new parts were then installed, 14 oz of PAG oil added to the compressor, 1 hour vacuum was done using a 6 CFM vacuum pump, after 30 minutes there was no vacuum loss and then system was then filled with a Snap-On A/C machine. 3.6 lbs of R134A was added. Everything has been done 100% to the book, twice now. But the A/C system continues to refuse to cool below 45 degrees on the highway, and continues to perform poorly for an extended time while driving down the highway.
I even went to the length of adding two, high-velocity, 12" electric puller fans directly attached to the back side of the condenser, thinking the condenser was getting not cooling well enough. It has helped bring the high side pressures down some, but has not offered a noticeable/worthy drop in outlet temperature.
My family owned a '98 Expedition from 2000 thru 2013. Never once serviced the A/C since new, and it never struggled to cool at idle, and blew 39-40 degrees out the vents without effort. This Navigator continues to take forever to cool no matter what I have tried.
Last week, we had a 98 degree day here in Maryland. I had a nice Covercraft windshield shade secured behind the windshield (these keep out a bit of heat compared to flimsy things you get at Walmart or the parts store), and my front windows are tinted to match the rear windows. So though it was hot outside, it wasn't exactly baking inside the car. I fired it up and let both A/C systems run full blast for 15 minutes. Got in the car and the outlet temp was 71 degrees. The car was still pretty warm on the inside, as 71 degrees coming out the vents doesn't cool as well as one might think in the hot sun. I drove the car for about 4 minutes to make it to the highway, and before hitting stop-and-go traffic, the outlet temp had gotten down to 63 degrees. Still not very cool, but did better now that I was moving. After about 8 minutes of being stuck moving from 0 to 10 MPH, the temp increased to 73 out the vents. A full 45-50 minutes after I started the engine, with the A/C systems STILL at full-blast, I was still crawling in traffic with only a 71-74 degree outlet temp. The car was still pretty warm.
Once I finally was able to pick up speed down the highway for a about 15 minutes I had gotten down to around 52 degrees outlet temp. This system is just struggling for some reason. I've owned 8 Fords since 2004, and not one of them has ever had a problem achieving 40 degrees or less out of the vents, especially when moving. Sitting still, I think 42 has been the warmest outlet temperature I've seen on any of my past Fords on a hot day. This one won't possibly below 70 sitting still on a hot day.
Even in inside my buddy's shop that was 72 degrees ambient temperature.... when we filled the A/C system to the 3.6 lbs, it still wouldn't get lower than low 50's coming out of the vents. We've clamped off both ends of the heater core and nothing improves. The rear system blows just about the same temperature as the front.... so it's not isolated to just one of the two systems.
What gives??? Nothing adds up here. The compressor isn't short-cycling, and nothing else seems to be acting up. When driving down the road on Sunday afternoon, it was 84 degrees out and I routed my R134A manifold gauge set thru the passenger's side window so my friend could monitor the pressures while driving. Low side was 25 PSI and high side was 196 PSI, and this was after 40 minutes of the A/C system running at full-blast.
Anyone with any solid suggestions would be really highly appreciated! At this point I have given up on it, but then every hot day while I sit in the car nearly sweating reminds me that I can't allow myself to have spent all of this time and money on parts and still be dealing with a hot cabin.
-Andrew