2003 Alero 2.2l - Using More Fuel
Have a 2003 Sedan, with 2.2l
Usually get 280-300 km by half tank (for a number of years now).
Recently though, mileage been worse (250 or less).
Problem started about 4 weeks ago.... 3 weeks ago replaced my cat after a rust hole emerged.
I replaced the O2 sensor - just in case.
I cleaned the Throttlle body, fund a gunky IAC piston in the process.
Ran FI cleaner through the tank.
No visible fuel leaks or odor.
No vacuum leaks.
Tightened intake bolts just in case.
Engine runs good, pickup good, idle even.
On the scanner:
ST trim jumps around a bit but avgs +5
LT trim - see up to +13.
Fuel closed loop.
If someone new was driving it, would not know there was a problem. BUT I know....
So what the heck have I missed?
Does anyone have some ST/LT trim comparisons?