07 Tahoe check engine light

[Richard Blakely]

Code says mixture too rich on bank 1. Runs ok and have replaced mass airflow, spark plugs and wires, o2 sensors. Air hoses appear to be good. Suspect pcv valve. Any additional items to check?

 

[Richard Blakely]

Correction to above. Mixture too lean not rich. Sorry about that

 

[swathdiver]

Code says mixture too rich on bank 1. Runs ok and have replaced mass airflow, spark plugs and wires, o2 sensors. Air hoses appear to be good. Suspect pcv valve. Any additional items to check?

What are your Long Term Fuel Trims at idle and while driving?

 

[Bill 1960]

Possible vacuum leak or injectors not performing?

MAF and O2 OEM?

 

[iamdub]

I'm with swathdiver and Bill. Check your LTFT and check for a vacuum leak. You said the air hoses (I assume you meant the PCV and brake booster vacuum hoses) appeared good, so it might be time to inspect (replace) the intake manifold gaskets. If you go there, check the VLOM bolts for tightness or, preferably, replace that gasket if there's any oil leakage. With the manifold off, if your rig has high mileage, you might wanna replace the oil pressure sensor as a PM (OEM only!) since it'll be super easy to access.

 

[Richard Blakely]

What is LTFT?

 

[CaptainAmerica1]

L=long
T=term
F=fuel
T=trim

 

[Richard Blakely]

Code says mixture too rich on bank 1. Runs ok and have replaced mass airflow, spark plugs and wires, o2 sensors. Air hoses appear to be good. Suspect pcv valve. Any additional items to check?

Local mechanic read odbc code. Apparently a more detailed code than Orielly showed. It showed a cylinder misfire on cylinder 5 (5.3l v8). Mechanic found the wire to plug was not on properly. He cleaned and fixed and cleared code. So far no problems. Need to test for 4-5 days to confirm fix

 

[CaptainAmerica1]

Good deal man. Glad you got it fixed, hope it’s permanent…

 

[Rocket Man]

Gott love the cheap and easy fixes. Woulda been free if you didn’t involve a mechanic.