Use the UV light on the a/c drain hose on the firewall.

 

Good thought, but I got the right set - R134a. It's not an issue of whether it connects to my car. The problem is the hoses they provided don't connect to the manifold gauge they provided. I'm thinking someone may have swapped hoses in the store with the R12 hoses or something and put the packaging back together.

This set only came with adapters for R134a. Here's what I bought:

NAPA AUTO PARTS - A/C Manifold Gauge Set - R134a -783420

 

Which side of the firewall would this be on? Engine side or passenger side? Or are you talking about the drip hose underneath the car where the wet spot always appears?

 

I am talking about the drip hose. It is on the passenger side of the firewall.

 

Those temps are close to normal, but a little low since air temp is low also. When temps climb to 80-90, it may be a struggle to get adequate cooling.

You have an R12 system and the manifold gauge set you bought was designed for R134a which has different size (much larger) fittings. Hopefully you can return.

It will probably take < 12 oz (1 can) of R12 to bring your system to normal. If it's been running Ok for some time, this may be low cost fix, but a can of R12 will probably cost $20-$30.

good luck

 

I found the short drip hose viewable from inside the car running into the firewall where it goes to the outside and drips onto the pavement. There is no sign of UV die inside the passenger compartment or underneath the car.

 

The car was originally R12 but was converted by a local garage 2+ years ago to R134a. I already tried to add a can of R134a but the pressure dropped from 33psi to 28psi - the opposite of what I expected to have happen.

My original post can be boiled down to this one question: if I added a can of R134a to my system and the pressure is less after adding the can than before it (28psi now vs 33psi before I started), does that indicate I have a leak somewhere?

Given that people seem to think my A/C vent temps are okay, I'm gathering people are concluding that I do not have a leak. Is that correct?

 

R134A set should have fit the connections. Did you connect high and low sides correctly?

That small difference (33 to 28 psi) in pressure after adding refrigerant says nothing. Was engine speed same, was compressor engaged, was fan speed same, was air temp same,...etc. Pressures can only be judged from experience and relative performance. There are no absolutes.

You may have a leak or not, but if leaking it is a small leak. A large leak causes system to quit cooling very quickly.

good luck

 

The problem wasn't fitting the car - I never got the hoses attached to the brass gauges (see attachment). The hoses wouldn't screw down - seemed like they were slightly larger than the brass threads from the gauge assembly.

Engine speed same - compressor was engaging - I believe the fan was turning on. The temperature was slightly warmer with the lower pressure reading, so I would have expected that to be higher rather than lower - based upon the chart that came with the gauge.

So is it worth keeping the manifold gauge (if I can get one that works properly)?



NOTE: Photo shows arrow pointing blue hose to red fitting. I was trying to fit the hoses properly - just goofed on the photo

 

Okay, so I finally got a gauge that works! Sorry about the delay. After letting the car idle with the gauges hooked up for about 5 minutes, here are the numbers I got today:

Air Temperature in the Shade: 89 degrees Dew Point: 55 degrees

With the compressor disengaged for about 15 seconds (every couple of minutes with max AC the compressor decides to disengage):
Low Side: 35 psi
High Side: 235-240 psi

With the compressor engaged at idle (about 600 rpm):
Low Side: 25-29 psi (No this is not a typo)
High Side: 240 psi

When the compressor was engaged boosting the idle to about (1200-1500 I'm guessing):
Low Side: 23-26 psi
High Side: 240 psi

Based on a chart I found online (not honda specific), it appears that normal ranges for my temperature should have been Low: 45-55 psi and high: 250-270 psi.

So what say ye all? Do I have a leak? Faulty compressor or what?