need a computer code analyed please

Bornstanger

Uncle 'Kiss Me''Kiss Me''Kiss Me''Kiss Me'er
Founding Member
Oct 20, 2001
476
0
26
Strongsville, OH
hey guys my stang would start acting funny when i would hit 3k rpms or so. then the check engine light came on. so i had the computer scanned at autozone and it pulled code P1131 for an air/fuel mix problem. could you guys in the know give me some more details as to this code and how i go about fixing the problem. any help would be much appreciated :nice:. thanx
 
P1131 Lack of Upstream Heated Oxygen Sensor Switch - Sensor Indicates Lean - Bank No. 1.


sounds to me like the front passenger side O2 sensor is the culprit . Anybody else got a better idea ??? lets help this guy out .
 
a bank 1 lean code could also be an intake vacuum leak or also possibly an injector seal leaking....just a couple more things to look for.....usually when an o2 goes bad it will throw a code for a lazy/stuck o2 (signal high/low or pinned)or something to that effect.....what would be helpfull is to get a look at the data stream to see how the o2 sensors are operating.....also while doing that......spray a little carb cleaner around the intake ports and injector seals to see if you get a change in engine rpm or a change in o2 sensor signal or both........hope this helps ya.....I have run into this before with a 5.4 expedition thought o2 was bad but after more diagnostics found the intake gasket on the drivers side to be leaking .....good luck...
 
yeah a little more info to help you guys help me figure this out. i really don't want to take this into a shop. i usually keep the engine below 2k rpms when it's cold and all. after it warms up i'll take it above 2k rpms, ya know romp on it and have fun like i'm supposed to with a nice V8 :D. anyhow before the check engine light came on, when i would get to 3k rpms, mainly around 3100-3300 rpms, the engine would sound like it's misfiring or something. it would make like a blatting sound, you could definately hear it through the exhaust note. i talked this over with my dad and he also suggested checking the air filter box, and the vacum lines. well i hope this helps with the solution here. thanx for all your help so far :nice: