I Solved My P0300!

[Dirk]

I had a p0300, and a p0171. my 05 1500 w/5.3l only has 27000 miles. I did a bunch of research and veryone was saying....it sounds like an intake gasket leak. I replaced it just to elimonate one thing. After....it ran the same.

 

Annoyed, i started thinking of the obvious. o2 sensors! I has a misfire on the entire left bank only. I swapped the o2 sensors from passenger and driver side. and sure enough the misfire chased the o2 sensor.

 

Change the sensor, solve the problem!

 

This is only my experiance. Not saying it is the same for everyone, but it should not be ruled out for all.

[DofD]

Congrats!

[kwad]

Hi have a 2005 Yukon with the 5.3, and I had the exact same problem at 30,000 miles. I'm beginning to think that year may have had a bad batch of sensors or something. If only you had posted your data 3 months ago....that would have saved me some grief, time, & dough. I'm glad to hear you were able to get it straightened out. Good job!