2004 5.4L - A/C System Questions

Disclaimer: Links on this page pointing to Amazon, eBay and other sites may include affiliate code. If you click them and make a purchase, we may earn a small commission.

stamp11127

Full Access Members
Joined
Mar 10, 2012
Posts
6,218
Reaction score
1,250
Location
Temple, Georgia
It all comes back to the basics. If you know how the system operates and the components that are utilized then you troubleshoot problems instead of tossing parts at them.

So, is the front ac working correctly?
 

1955moose

Full Access Members
Joined
Nov 23, 2014
Posts
5,981
Reaction score
1,338
Look Princey boy, would you just throw parts at an elaborate computer your working on, in hopes it might fix the customers problem? No of course not, you'd go through the regular diagnostic for the issue your customer was having, whether it's a total lack of power, or something more simple. Mechanical issues are really no different, theirs a flow chart. You start at symptoms and troubleshoot from there. You already have a leg up on some of our other members in that you have the electrical knowledge and can troubleshoot and read schematics. Like Stamp said read up on how air conditioning works, then you'll understand how to troubleshoot your system. You might want to spring for a Ford repair cd online, all will be on it!

Sent from my N9131 using Tapatalk
 

1955moose

Full Access Members
Joined
Nov 23, 2014
Posts
5,981
Reaction score
1,338
Ain't that the truth!

Sent from my N9131 using Tapatalk
 

stamp11127

Full Access Members
Joined
Mar 10, 2012
Posts
6,218
Reaction score
1,250
Location
Temple, Georgia
1955moose if one "Millennial" is getting under your skin you should try teaching. My class size is usually around 14 & most complain about spending $350 on a book - then state they don't understand it and refuse to read it. I point out we are only covering @600 pages in 12 weeks plus labs. What is the big deal? And you need to stay caught up.
Normally there are 2-3 students that are there to learn a trade so our time isn't wasted. The rest of them are for my entertainment....
 
Last edited:

1955moose

Full Access Members
Joined
Nov 23, 2014
Posts
5,981
Reaction score
1,338
I actually get along pretty well with young men/women. The fact I'm 63 going on 18 doesn't hurt. The thing that drives me nuts though, is right smack in the middle of a conversation they have to see what's going on with their I phone. I had a young lady I was riding this morning on my bus, and I lost her 5 minutes into the conversation. I guess I turned into my father without realizing it!

Sent from my N9131 using Tapatalk
 

Prince_Polaris

Full Access Members
Joined
May 11, 2018
Posts
184
Reaction score
21
Location
Maryland
It all comes back to the basics. If you know how the system operates and the components that are utilized then you troubleshoot problems instead of tossing parts at them.

So, is the front ac working correctly?

Yeah, sorry, I'm a bit strange, I tend to get frustrated with new things if I don't know everything right this second, it's a bad habit... growing up as a gifted child goes bad pretty fast because for years you don't need to study or do anything because you already know everything, and when your scope of knowledge suddenly isn't big enough, it's a disaster :/

-------------------------------

Anyway, yes, the front AC works fine. Since it was cold this morning, I tested the heat, and I do have working front and rear heat, thankfully, that will be nice this winter...

So, the front AC works, and surprisingly, it works best at highway speed, despite reports here on the forums about how highway speeds will make it stop working, due to the air pressure problem that you're meant to solve with an elbow... joint? I think that's it, the pipe thing.

The rear AC however, does not. It doesn't blow hot air, it's just simply not cold, like a fan you'd sit on your desk, it just blows the air. Also, there is a constant hissing from the rear when the AC is on, and it increases and decreases with what I assume is the fluctuations of the AC system.

It just confuses me, because... if it was a leak, a leak bad enough to hear the hissing, surely it would've leaked enough to stop my front AC from working, right? I read somewhere else on the forum (perhaps it was you, moose...) that if you're a bit low, the rear will stop working first, and all you need to do is add refridgerant to get it working again.

Normally, I would say something along the lines of "It's not that important because it's usually just me", however, our 07 chrysler van is once again broken, so I'm the family transport for now, and since me and my brother sit in the front, my parents aern't too happy with the nonfunctional AC, so I'm either hoping that it's an easy enough fix for me and my not-so-good-skills to fix, or that we can at least find out what's wrong so I can take it to a shop and save them from having to diagnose it themselves....
 

stamp11127

Full Access Members
Joined
Mar 10, 2012
Posts
6,218
Reaction score
1,250
Location
Temple, Georgia
A good shop will take your input diagnosis then diagnose it properly so they only fix it once.

I'll go out on a limb here and assume you don't have the specialized equipment to needed to repair the ac. If you want to give it a shot though decent starter sets are around $400. And if the part I think has failed actually has, it is @$35.

If you have a leak, adding 134a is just a band aid.
 

1955moose

Full Access Members
Joined
Nov 23, 2014
Posts
5,981
Reaction score
1,338
Wasn't me on the A/C diagnosis. Their is a valve and washers in the rear that go bad, I think that's what Stamps referring to. You have to pull apart passenger rear panels to access. You may have to have shop at least withdraw your freon, and possibly do repair.We warned you before you bought this Suv to have dealer fix all the loose ends before you took delivery. Well maybe that warranty they gave you will work.

Sent from my N9131 using Tapatalk
 
Top