2003 250 6.0 FX4 Lariat....When I first start the truck and turn the a/c to max it blows out of the defrost for probably about 45secs and then it will blow out of the vents. I have figured out that if I turn it to a/c it will blow out of the vents and then I can turn it to max. Plus it does not seem to be as cold as it was before, it seems to get colder while the RPMs of the engine are higher than if I stop and the engine idles. Any ideas, its hot in South Carolina!!!!!

Bigsmoothe49 said:

2003 250 6.0 FX4 Lariat....When I first start the truck and turn the a/c to max it blows out of the defrost for probably about 45secs and then it will blow out of the vents. I have figured out that if I turn it to a/c it will blow out of the vents and then I can turn it to max. Plus it does not seem to be as cold as it was before, it seems to get colder while the RPMs of the engine are higher than if I stop and the engine idles. Any ideas, its hot in South Carolina!!!!!

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Sounds like you have a control head problem. Its not getting the vacuum to the actuator on the mode door. It gets cooler because you have air flow going through the condenser. Possible cooling fan issue, low freon charge, broken fan shroud, debris blocking the condenser.

About a week ago I added two cans of freon and there was no difference. The shroud is fine and I dont see anything blocking the condenser. Keep in mind that it has been blowing cold just not cold enough to where I have to turn it off of max. Just today I am on a 200 mile one way trip back home on I-95 and there is no "cool" air blowing out of the vents. I pull over smell something electrical burning and I notice that the 3 front bolts on the a/c clutch are red hot and glowing. Please help

If the bolts are red hot it sounds like the clutch on the compressor is siezing up wyhich would explain why you have no cool air now.

You probably overcharged it when you put 2 cans in it which caused the compressor to lock up and that's what burned up your clutch. The system on my '95 only holds just under 3 cans as do most systems. You're going to have to replace the clutch now and I would discharge the system and start over.

Snap, I had a lady in a caddy come by the other day with it not cooling. I checked the pressure and it was high, then I looked at the condenser coil and it was full of bugs, grass, and just about anything that could get stuck in one. I cleaned it out and the pressure dropped and it got cold in there.

I can change the clutch. Do you think that I will still have an issue with blowing out of the defrost first? If the clutch was starting to mess up would that cause some of my original issues?

Bigsmoothe49 said:

I can change the clutch. Do you think that I will still have an issue with blowing out of the defrost first? If the clutch was starting to mess up would that cause some of my original issues?

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Thats a vacuum issue with the defrost. Its designed to default to defrost in case of vacuum loss.

radialarm said:

Snap, I had a lady in a caddy come by the other day with it not cooling. I checked the pressure and it was high, then I looked at the condenser coil and it was full of bugs, grass, and just about anything that could get stuck in one. I cleaned it out and the pressure dropped and it got cold in there.

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Yeah, no airflow through the condensor will contribute to high side being too much, and no cooling.

Bigsmoothe49 said:

I can change the clutch. Do you think that I will still have an issue with blowing out of the defrost first? If the clutch was starting to mess up would that cause some of my original issues?

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It might have been a clutch problem, but I think over filling the system killed the clutch. almost 5 cans is way too much. (almost 3 cans normal fill and 2 cans you added.)

blacksnapon said:

Thats a vacuum issue with the defrost. Its designed to default to defrost in case of vacuum loss.

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I agree with this^. It is normal for your A/C to blow through the defrost for a few seconds until your engine creats enough vacuum.

As far as your cooling issue. You need to check the vent temp. with the A/C on max. It should be around 37*. R134 systems are tricky on the amount of freon too little or too much will result in poor cooling. I usually add freon until I get to near the specific amount, then slowly add more until I get the temp. I'm looking for, but never more than the sticker on the truck says. It helps to have a fan on in front of the condenser coil when checking the vent temp.

Ok. Where and how should I start trying to troubleshoot where the vacuum problem is at? Thanks for all the info!!

Everything in your first post sounds normal. I don't see a vacuum issue. All R-134 systems cool poorly at idle. That's why I put two efans in front of my condenser coil. Check and see if your model truck has cabin filters. That might be the problem if they're dirty. The only sure test is your vent temp. as I described earlier.