System Too Lean

Idle speed may be too high or too low. Engine speed may vary up and down. Disconnecting IAC does not help. This may set Code 44. A "Scan" tester and/or voltmeter will read an oxygen sensor output less than .3 volt. Check for low regulated fuel pressure or water in fuel. A lean exhaust, with an oxygen sensor output fixed greater than .8 volt, will be a contaminated sensor. This may also set Code 45.