HI,

My 2008 is showing P0171 and I am wanting to track down potential vacuum leaks.

I have a vision problem that allow me to see at 6" and at 10', but things are hard for me to see in the middle ranges especially in dark places like behind the motor.

Can anyone help me out by narrowing my search for places where I might have a leak? I did find the NPP connector by the brakes but am not sure where else to look for obvious leaks. The car has 40,000 miles and has the stock tune. It has a Calloway air filter and MAF. The air duct is tight to the frame and looks OK, but???

I just measured the vacuum at the NPP by the brakes and it is 17" which I think is a little low, but have not worked on the LS3 before, so not sure what is normal. The manual says 16" to 23". I'm used to seeing 23". The NPP works normally.

I can't clear the code without disconnecting the battery. (tried a Diablo tuner and two after market OBD scanners). After I have cleared it, it will throw the code at idle in about 5 min.

I'm leaning towards the O2 sensor on the left side and have one coming in. I have read most of the threads and lean towards the O2 sensor as it only throws P0171.

Can any one steer me to where to look for leaks?

I am getting straight 'A's in braille driving.

Thx,
Dave

 

171 code is for the driver side of the engine. what engine do you have? for the light to turn on after 5 minutes, something is loose or unplugged. did it happen after the CAI install ? has the intake manifold been off ? I would start by checking clamps. I would follow by inducing smoke into the intake manifold and look for a leak.

 

I know it's only one bank, so far, and lean not rich, but have you considered an over oiled air filter getting the mass air flow sensor dirty?

 

Where can I look for potential vacuum leaks?

I've got a vision issue.

Thx,
Dave