Where is the low side line to add refrigerant to a 1998 grand cherokee

probably a broken vacuum line under the hood or under the dash. had the same problem with a 97 cherokee found a broken vacuum line on the passenger side firewall under the hood behind the a/c .

They should be located directly on the back of the compressor and i belive the bottom one is the low pressure side. Hope this helps.

Follow the AC lines and look for a plastic cap. There are 2, The big one is the high side and the smaller one is the low side. Unscrew cap to add freon.

Capacity is aprrox 1.75 lbs with proper gauge (28 ozs). Leak points are many, low side port ,high side port, high and low cut off switches,evap inlet,compressor manifold,condensor inlet and outlet...to name a few.

134a. which is used iv all vehicles after 1995

ac lines under the hood carry r134 through the ac system. there are high pressure lines and low pressure lines. each side has an opening for service. it is not uncommon for the system to lose refrigerant and either be less efficient or not work at all. to add freon to the system runs the risk of overcharging which will cause the system to run less efficient and possibly cause damage to the compressor or seals. the charging or adding of freon is always done to the low side and you can identify the low side by the size of the line. you will see there are two obvious sizes of lines. find both connection points first and make sure you know you are dealing with the larger lines which is the low pressure side. attaching to the high side could cause a can to explode and you could be injured!! with the engine running and the ac on its coldest setting with the fan at maximum speed you open the freon can with it in the upright position. verify that the compressor is engaging the clutch on the compressor. cans usually contain about 12 oz of freon. stay away from the mixes that try to give you stop leak and lubricant. try one can and see what you get. about those lines the size of the high side is like a pencil and the low side is like a magic marker. that should help you identify them. if you need more please reply and good luck

Add the refrigerant to the low pressure side of the ac system while the ac is turned on.

check your fluid. you may need to add fluid because when the fluid gets low it doesn't have the pressure needed to engage the transmisson gears and valve bodies.

go here. http://i5.photobucket.com/albums/y192/fonzz300/P1000436.jpg that should be it

It's the one with the blue cap. Your hose won't fit on the high side, so you're safe.