i got a code off my 1997 mercury cougar.. it was po172 and p1443....the motor studdars during driving....i looked up the p0172 code and it said the emissions control system. ive replaced the charcoal canistor purge valve and code still appears...and p1443 i looked up as well and it states im toop rich in bank 1...do these codes tie together somehow.....i cleared the codes today wit a scanner and they appeared right away.....please any suggestions will help greatly