R-134a Conversion VFAQ

This is how I did the conversion on my 90 FWD Turbo Eclipse. I am assuming that all 1st generation cars will be the same but I am not sure. This "modification" is done at your own risk and I assume no responsibility for your actions or damage to your car.

Make SURE your AC system is empty before attemping the conversion. For anyone with a "weak" but functioning AC simply screwing on the adapters and adding in the R134 will do more harm than good. Don't vent your existing R12 to the atmosphere. Aside from being a hazard ecologicaly, it's very bad for your lungs. Take your car to someone local who can pull a vacuum on the system. It will accept a better charge anyway. (excerpted from Steve Blake's post to the 7/9/98 digest)

I have not heard conclusive information on the mixing of R12 and R-134a, but when the new refrigerant came out it was said many times that the two could not mix. As Steve said above, I would not reccomend adding 134a to a weakly functioning R12 system. The jury is still out on longterm damage to the compressor and other A/C components. If anyone finds information on this email me and I will add it to the page.

When I did my car there was absoulutely NO freon in it. I pushed the valve and nothing went in or out. I was amazed that when I got the new freon in that system worked at all. Every car will be slightly different in its reaction and perfomance so good luck.

There will be three adapters in the kit. You need two, the other one is for some GM cars. The adapters can only go where they are suppossed to so you really can't screw it up.

You can click on any of the pictures to see a larger one.

UPDATE : As of May 17th, 1999, I have had r134a in my car for ten months.  I have noticed no decrease in cooling ability or any adverse effects to the A/C system.   Just recently I have started using the A/C quite a bit, and it works flawlessly.

NEW : Someone from the digest wrote me saying that he had some questions about removing the existing oil from an r-12 system.  He found this site that you may want to check out to answer any questions.  It is very thorough.


High Side First off attach the new adapter to the high side fitting. It has thread lock on it so once it is on it stays. I didn't even need any tools to put it on, just twisted it with the red cap.

Low Side Next screw the adapter on to the low side. On my car it is located on the compressor itself. Kind of a tight fit for your arm, so do it when the car is not running. I had a little trouble getting it tight, but a little work with an open end wrench fixed that. In the picture the fitting has a light blue cap on it.

R134a Can with 
hose. This is the can with the special hose attached. On the side that attaches to the can there is a metal pin that breaks the seal on the refrigerant can. On the other side there is a quick disconnect fitting that will only fit on the low side connector.

Charging the system (1). Turn off the engine, reach down to the low side fitting (on compressor) and attach the quick disconnect fitting to it. After it is connected, start the car and turn the A/C on full blast. Turn the knob on the can end clockwise as far as you can, then turn it back all the way counter clockwise. This breaks the seal on the can, this must be done with every can including the oil charge. The first two cans need to be "poured" into the system. That means just hold them upside down (like in the picture) until they are empty. After the first two are in add the oil charge can in the same way. Now you are ready to add the final charge. When removing the hose turn off the vehicle first because the belts are right where your hand needs to be and that could be very painful.

Charging the system (2). The third and final can needs to charged standing right side up (see picture). I am not sure why, but it worked when I did it. When the A/C system doesn't seem to be pulling anymore freon out, or five minutes have passed, remove the hose and can. To do this turn off the car turn the valve full clockwise until it stops, and then remove the quick disconnect fitting. The manual says to remove the hose quickly and put the included cap on the can. I just left the hose on the can with the valve tight. I don't think it has leaked yet.

side with service cap. Next put the service caps on the ports. Use the red one for the high side and the blue one for the low side.

r134a alert sticker. Finally, put the sticker that came with the kit that alerts a mechanic that the system has R134a instead of R12. I put mine by the engine description sticker on the underside of the hood.

The pictures with the can in them and the picture of the sticker were taken with a Casio QV-10a digital camera. If you are thinking of buying one DON'T. The other pictures were taken with an Olympus D-500L. Even with these pictures you can see the quality difference. All the pictures were ran through Paint Shop Pro 5.0 and were saved as jpg's with a 20 compression factor.

If you have any comments or questions about the page please email me.