I tried to recharge my ac on my 2003 buick century. The only port I found was a large tube dead center and against the firewall that came up neared the hood, and curved back down & with the port at the top of the curve. But the connector would not fit. Where would the other port be located?

I tried to upload an image oimage tube I found, but upload would not work, only alert with ok showed

thanks

The port you use is the low side which is the larger line. The cap should be blue. You need special equipment to charge from the high side (red cap) near compressor.

That was the correct port. I had a customer that was a mechanic recharge the AC. He even had a hard time putting the connector on.

Is it working properly now?

what is the usage of your gauge set for? A r134a gauge set has a larger fitting than the r12 gauge set for the low pressure side. The fitting is larger, subsequently, to make it so the low and high side ports only work on their proper ones. R12 can be accidentally reversed.

My set is r134a and r22

alsp, if the outside is dirty or the inside has any debris under the cap or if the cap broke on removal it may have left some in the port not allowing the gauge fitting to snap on.

akso if the port was full of stop leak or the gauges had a mess at the port when charging the snap function of the port may have gummed up not being cooperative on attempted use. I could see a fitting that was stripping the threads at an angle slightly when installed being leak free but distorted the fitting so it doesn’t play nice. So it would effect the mechanic too. Check for anything bent or if it’* at a 90degree like intended