My ac blows out hot air.. i charged it and it wil work fine for a day and then blow hot air.. where and how would i check for a leak?? and if so .. how do i fix it?

 

I recommend you take it to a good A/C shop, one that does nothing but A/C and is BUSY.
Explain that it won't hold a charge and that you want it sniffed for refrigerant.....they'll go over all the connections with the sniffer.

 

It your evaporator core. The one in my 96 Explorer crapped out two years ago. You have a 98 = 8 years old - same as mine was. I had the same thing happen to my 93 F-150 5 years ago. Again 8 years old. These things seem to last about 8 years before failing. I also replaced the compressor on the F-150. I did not on the Explorere but just yesterday I noticed it was beginning to get noisy so I expect it will fail soon. Have an AC shop do this. It costs a bit but it gets done right.