I have been getting a P1120 code. Had it checked at autozone. They said it was a dealer fix..... What is the code. the reader said something about air fuel metering.....P1120 I think it has something to do with the TPS sensor... I replaced the IAC 7000 miles ago I have a 1998 EXP XLT with the 4.0 SOHC, 108,000 ,4X4 Please help me fix it or do I need to go to dealer?