Main IndexAuto Repair Home Search Posts SEARCH
POSTS
Who's Online WHO'S
ONLINE
Log in LOG
IN









Search Auto Parts

A/C Help !


  Email This Post



mahgnibb
New User

Jul 25, 2022, 8:44 AM

Post #1 of 8 (230 views)
A/C Help ! Sign In

2010 Ford Expedition

Having issues with A/C system....here is where I'm at:

Over past year, have put in a few cans of R-134a, would get some cool air for awhile before returning to only warm air.

Over the past few weeks, have gotten more sophisticated in my target shooting:
1) had system evacuated of freon
2) ran a vacuum for about 30 and it seemed to hold -30psi overnight
3) put in 10oz. of r134 with a dye
4) also put in 20 ozs of r134 (car holds about 32 ozs)

Currently: Air cools to about 58 degrees.
High pressure side goes between 175 and 275 PSI as the compressor kicks on and off.
Ironically, i dont see any pressure on the low side (i.e., about zero).

In inspecting the system with infrared light to identify the dye, there appears to be a potential small leak near the bottom of the condensor and/or the line that goes from compressor to condensor (i think).

Seems like a few issues are present...based on what i've researched,...could expansion valve be blocked (thus zero pressure low side)? But why does it seem to still cool (for now) to 58 degrees?
a small leak likely by condensor.

i havent tried the soap/water test yet to further see about leak....

anything else suggested and/or possible issues given the above?

i'm really trying to evaluate everything before deciding if the repair is doable myself, or bit the bullet and bring in.

On a side note...the car has 200K miles so A/C issues are no surprise with this mileage.


Tom Greenleaf
Ultimate Carjunky / Moderator
Tom Greenleaf profile image

Jul 25, 2022, 10:42 AM

Post #2 of 8 (215 views)
Re: A/C Help ! Sign In

For leak ask a shop to use a sniffer to find it if you know rough location that would help prove it see how fixable it is or a new condenser?
Performance is going to be strongly related to ambient temp so means little right now.


What is it in front of the truck's grille away from engine heat?


Low side ports can't get a reading but could add refrigerant try pushing down on you gauges ZERO if while running if cools at all is impossible actually. Try again also engine off for a static pressure, engine cool/cold should be close to actual area temp in F. or above.
Post those would really help.


BTW - holding a full vacuum is just a good clue to charge a system. That vacuum is only hold OUT about 14.7 PSI or atmospheric pressure give or take - not much vs pressure of gas in the system,


T



Hammer Time
Ultimate Carjunky / Moderator
Hammer Time profile image

Jul 25, 2022, 11:50 AM

Post #3 of 8 (205 views)
Re: A/C Help ! Sign In

Does the low side gauge show pressure when the system/car is shut off?



~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

We offer help in answering questions, clarifying things or giving advice but we are not a substitute for an on-site inspection by a professional.



Tom Greenleaf
Ultimate Carjunky / Moderator
Tom Greenleaf profile image

Jul 25, 2022, 12:05 PM

Post #4 of 8 (198 views)
Re: A/C Help ! Sign In

I asked that named "static pressure" about like taking tire pressure OP. You were able to charge it do this isn't making sense yet. I've had several other than gauge/set just refuse? Need 3 hands hold those pushed down will usually read - try that then quit when you stop - it's annoying,
Tom


mahgnibb
New User

Jul 25, 2022, 8:14 PM

Post #5 of 8 (173 views)
Re: A/C Help ! Sign In

Thanks for the comments/suggestions above.

I too was puzzled about the zero reading on the low side....i disconnected, opened/closed the ports on each dial that connected to the high/low side...

initial reading was 100 high and low (engine off) and car sitting for 1 hour.
Temps in garage (doors open) were about 82 degrees.
turned car on...
gauges (low/high) basically oscillated between 30/150 (for about 30-40 seconds), then increased to 38/270ish (compressor ran for about 30 seconds during this interval).
The times for compressor on/off cycled pretty consistently as did the ranges (30/150, 38/270)....

so seems like the gauges are working better now.

when i had the car on the road earlier, vent temps got as cold as about 47 degrees. While i was on pressure gauges, a quick reading it dropped to about 55 degrees. i upped the idle a bit,...but didnt want to run too long in garage for obvious reasons (again, doors open).

so, do these ranges seem normal ? and running times of compressor on/off?
to me seems like things are working fine, but i suspect the target shooting im' getting back to is where i think i've identified there is a leak (with a faint view of the yellow die)...on the tube near compressor to condensor, and also below the condensor on the pan.
i may only have a few days left of my AC working again...until it leaks enough for a/c to go warm again.

does all this seem like im on the right track?
Thanks again!


(This post was edited by mahgnibb on Jul 25, 2022, 8:15 PM)


Tom Greenleaf
Ultimate Carjunky / Moderator
Tom Greenleaf profile image

Jul 25, 2022, 9:41 PM

Post #6 of 8 (165 views)
Re: A/C Help ! Sign In

Those are now credible for the ambient temp when working. Best to do outdoors if you can IDK about in a garage what air or dangers there could be for you.

Cycling could be normal for where it is.

Essentially I see this as finding that leak and fixing it.

Other things to check and fix: Condenser clean of bugs or whatever. If you have a dirty setting (leaves, pine needles) clean them out and try to look in between condenser and radiator.

Fan(s) working properly? Do they speed up if you notice? It's not that hot as you listed vs some areas it's the situation right where you are working that matters.

A/C is a real b*tch of calculations, live as it's happening in front of you takes knowing all temps LIVE when one is an issue or rule out that it's normal the situation isn't?

Tom



Hammer Time
Ultimate Carjunky / Moderator
Hammer Time profile image

Jul 26, 2022, 4:12 AM

Post #7 of 8 (152 views)
Re: A/C Help ! Sign In

There are two issues with what you are saying

1) Those pressure are not normal and too high
2) This is not a cycling system and should not be turning on and off

If you are sure you put the correct amount of refrigerant in the system, it takes 33 ounces not 32, then you need to check the fan operation carefully. This is a 2 speed fan system and it sounds like it has lost low speed. This is likely what you are seeing is high speed kicking on and off and not the compressor.

This fan circuit uses 3 relays and is rather complex. The first thing you need to do is test all the fuses with a test light.



~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

We offer help in answering questions, clarifying things or giving advice but we are not a substitute for an on-site inspection by a professional.



Tom Greenleaf
Ultimate Carjunky / Moderator
Tom Greenleaf profile image

Jul 26, 2022, 6:14 AM

Post #8 of 8 (145 views)
Re: A/C Help ! Sign In

Top post quote ">4) also put in 20 ozs of r134 (car holds about 32 ozs<"

That was the clue all along. Can't guess at this like OLDER stuff. Spot on or all hell.

Sensors to shut off with unseen high heat sensors or super low pressures both also mean what temp it is and where.

I just smell this is OK if it had the right charge and quit pulling hair out.

Fuses and relays should all just plug in. What's the corrosion just plain look like on the spades and where they plug in? Looks alone not the whole story some just pulling out and back in work properly or a whack with plastic end of a screwdriver - THAT'S THE ONE for the moment if that works.

If one it's all of them exposed so something even just water, worse if a rust area or ever was there.

NOTHING IS VALID WITHOUT KNOWN CORRECT CHARGE, BY WEIGHT INTO A WELL HELD VACUUM IF IT ONLY WORKED PROPERLY FOR A HOUR THAT'S INFO.

A/C is a pest on all fronts, not DIY friendly on all fronts doesn't always mean shops know their sh*t either (around me) it's not profitable and seasonal, the space to do it is so costly it's just not worth it and put all the crap away off season is most of a year,

Tom







  Email This Post
 
 


Feed Button




Search for (options) Privacy Sitemap