: P0411

12-02-12, 10:58 AM
Hello i have a 2001 Cadillac Catera 3.0 been trying to fix this for awhile here is what i have done i have replaced the Air By-Pass Valve,Air Check Valve,Mass Air Flow Sensor,done a smoke test on the vaccum lines checked if the air pump was running and blowing air because i took off the line at the pump to make sure it was working there was alot of forced air comming from teh pump.Someone said it could be bad Oxygen Sensors if it could be that how many of them are there on this car. i have a code reader INNOVA 3100E with Freeze Frame here is the Data. i posted the pictures i hopes it helps.thanks everyone.

12-03-12, 12:43 PM
I just had a P0411 last month that I got rid of by putting a can of STP fuel treatment in. I've had the car a long time, and I vaguely remember doing this a couple times before as well.

There are four O2 sensors, two after the exhaust manifold and two after the Cat converter. Usually, the O2 sensors give you their own codes.

12-03-12, 05:03 PM
Fuel system cleaner will have absolutely no effect on a P0411 code, or the O2 sensors, or any component of the A.I.R. System.