Need A/C help

T

twinsnakes23

New Member

Oct 13, 2004

23

0

2

Jul 22, 2010

#1

• Jul 22, 2010

• #1

I have a 90 Mustang and I recently converted my a/c to R134. I bought all new parts compressor, condensor, lines, etc. In the morning and evenings the a/c blows very cold. During the day in 90 degree days at idle it only blows cool air and on the highway the a/c is cold, but I think it should be colder. The biggest problem is at idle. The cool air just isn't enough to cool the car on these hot days. I just bought a new fan and clutch and my car never runs hotter than 200 degrees but somehow it doesn't seem to be enough to keep the a/c blowing cold air. I thought about replacing the stock fan with a taurus fan or running a fan in front of the condensor. Anybody have any other suggestions?

 

jrichker

StangNet's favorite TOOL

In Remembrance. Thank you for your contributions

Mar 10, 2000

27,512

2,811

234

Dublin GA

Jul 22, 2010

#2

• Jul 22, 2010

• #2

Did you vacuum the system down throughly before charging it? You need to pull a minimum of 28" of vacuum for 30 minutes.

 

HISSIN50

"How long does it take to get help in here?

15 Year Member

Nov 29, 1999

31,179

33

129

Jul 22, 2010

#3

• Jul 22, 2010

• #3

If you have a big box fan blowing in front of the car, does the AC performance improve?

 

T

twinsnakes23

New Member

Oct 13, 2004

23

0

2

Jul 22, 2010

#4

• Jul 22, 2010

• #4

Yeah as soon as I but a fan in front the a/c blows cooler. I just don't know why the stock fan isn't enough cause it was fine for years before the old R12 system went out.

 

T

twinsnakes23

New Member

Oct 13, 2004

23

0

2

Jul 22, 2010

#5

• Jul 22, 2010

• #5

As for the system, I had a shop do the work and they say the system is working fine. They say I just need a better fan, but like I said the stock fan used to be enough with the old R12 system. I just want to see if I can fix the problem with the stock fan before changing to an electric fan.

 

jrichker

StangNet's favorite TOOL

In Remembrance. Thank you for your contributions

Mar 10, 2000

27,512

2,811

234

Dublin GA

Jul 22, 2010

#6

• Jul 22, 2010

• #6

R12 & R134 have different cooling characteristics. They do not act the same when used in the same system. R134 needs a larger condenser (A/C coil in front of the radiator) to properly condense the gas into a hot liquid. As a result, R12 systems converted to R134 don't cool as efficiently as a system designed for R134. If it becomes a serious problem, you might want to consider adapting a condenser from a 94 or later Mustang. This will involve some flaring of the lines for new fittings, fabricating some connections and mount brackets. You will need to do a vacuum down and recharge once the fabrication work is finished..

 

T

twinsnakes23

New Member

Oct 13, 2004

23

0

2

Jul 22, 2010

#7

• Jul 22, 2010

• #7

I'm guessing my best bet would be to put a fan in front of the condensor to keep my A/C blowing cold while at idle.

 

LiquidGT

Member

Oct 8, 2007

368

0

16

Near STL hell

Jul 23, 2010

#8

• Jul 23, 2010

• #8

Actually when I went to a Taurus fan my a/c benefited as a side effect, my a/c performance used to be like what you described in your first post with a stock fan and a Black Magic fan. With the Taurus fan it still doesn't get "too cold" like a newer car, but I don't sweat like I used to with the A/C on either on a 90* day either. I'm sure a Sn95 condenser would help the old Fox systems too.

A small fan (like the deals they sell at Autozone) in front of your condenser should help out and would be simpler than a Taurus fan if you're not confident with wiring. I would still upgrade to a 3G alternator if you haven't done so.

Unfortunately I cant figure out why my car sometimes stalls when I release the clutch when coming to a stop with the A/C on??? So I'm leary on when and where I use it.

 

HISSIN50

"How long does it take to get help in here?

15 Year Member

Nov 29, 1999

31,179

33

129

Jul 23, 2010

#9

• Jul 23, 2010

• #9

LiquidGT, do you have any IAC or VSS issues?

 

LiquidGT

Member

Oct 8, 2007

368

0

16

Near STL hell

Jul 23, 2010

#10

• Jul 23, 2010

• #10

HISSIN50 said:

LiquidGT, do you have any IAC or VSS issues?

Click to expand...

I thought about the VSS and its the only thing I havent tried messing with. Last summer I ran through the checklist, swapped a new IAC for a while, ran the codes, the freon isn't low... nothing. I grabbed one of those IAC adjuster plates and it seemed to help last year... but not this year.

Some days it works well and some days it wants to act up, more so when I come from a more aggressive stop or down a hill at max vacuum.