Low Idle and running lean

[Alan H Stott]

Hey all so I am hoping someone here knows what is going on and how to fix it.

Recently My engine has started to run lean and I am seeing the idle extremely low. My dad does not think it is a vacuum leak and told me to clean the intake and clean the filter.


I run the code it says it is an O2 sensor and so I replaced the sensor and it is still showing the same thing. I also am replacing the fuel filter and another O2 sensor.

When the codes pop

*They read low flow and running lean
And
* Random Misfire detected
And indicates an O2 may be the problem.

Has anyone had experience with this issue?

 

[Fless]

Post up your vehicle info: year, engine, mileage, last tuneup, etc. and list all of the current (not history) code numbers. That will help us get started asking more questions.

 

[Doubeleive]

if you are at 160k or more I would take a really strong look at the maf, it can cause your reported issue's and at 160k is generally when they start taking a shit. you dad is on point

 

[Alan H Stott]

Post up your vehicle info: year, engine, mileage, last tuneup, etc. and list all of the current (not history) code numbers. That will help us get started asking more questions.

Okay so I am sorry about the delay in reply I had to do a bit of work irl (unrelated)
My Truck is a 2004 Chevy Tahoe LT 5.3 V8 w/E85 FF Tech it is the 1500 series it has 256,904 miles on it and current codes are P0300 Random Misfire Detected
And P0171 System to Lean <---This one throws 2 times and it says most likely solution is to clean the fuel injectors. So I just put Lucas injector cleaner in on a half tank and the AZ tech said to run it till empty and gas up on E91 and use a second one to finish it off with the cleaning.

 

[Alan H Stott]

Okay so I am sorry about the delay in reply I had to do a bit of work irl (unrelated)
My Truck is a 2004 Chevy Tahoe LT 5.3 V8 w/E85 FF Tech it is the 1500 series it has 256,904 miles on it and current codes are P0300 Random Misfire Detected
And P0171 System to Lean <---This one throws 2 times and it says most likely solution is to clean the fuel injectors. So I just put Lucas injector cleaner in on a half tank and the AZ tech said to run it till empty and gas up on E91 and use a second one to finish it off with the cleaning.

 

[Doubeleive]

if the maintenance history is unknown I would put in new plugs & wires and drivers side forward 02 sensor. that should address the codes but it could also need other things like coil packs or a maf sensor. at that mileage you are probably going to have to do a lot of maintenance if it hasn't been kept up.

 

[Tonyrodz]

if the maintenance history is unknown I would put in new plugs & wires and drivers side forward 02 sensor. that should address the codes but it could also need other things like coil packs or a maf sensor. at that mileage you are probably going to have to do a lot of maintenance if it hasn't been kept up.

The oxygen sensor for the lean codes? Is there a code for a bad o2?

 

[Doubeleive]

Lean code would be the sensor or cat, cheaper and easier to do the sensor first, or low fuel pressure or maybe a vacuum leak somewhere.

 

[Alan H Stott]

if the maintenance history is unknown I would put in new plugs & wires and drivers side forward 02 sensor. that should address the codes but it could also need other things like coil packs or a maf sensor. at that mileage you are probably going to have to do a lot of maintenance if it hasn't been kept up.

History is unknown. I really hope plugs and wires and coil packs do the trick.

 

[Alan H Stott]

The oxygen sensor for the lean codes? Is there a code for a bad o2?

There was at one point same codes too which is weird