I have the following CELs:

p455 - EVAP major leak
p1136 - system too lean bank 1
p1138 - system too lean bank 2

I've done the following but cannot clear the codes:
+ new MAF sensor (improved throttle response, but codes still there)
+ new gas cap
+ replaced vacuum lines a year ago
+ with engine running sprayed brake cleaner all around the intake manifold area and vac lines, but no idle increase

Also, the EVAP purge valve on top of the air box is not clicking. I have a new one arriving tomorrow.

Assuming the purge valve doesn't fully fix the issue, how do I properly check for vac leaks?

I'm wondering also if there is a hole in the EVAP lines or Leak Detection pump. Any chance I can do some kind of smoke test with spray smoke or cigar smoke like in the obnoxious youtube video? I'm not sure what lines to connect to.

I'm driving 1500 miles this weekend and don't want the motor running lean.

 

This is the obnoxious cigar video -- not sure if it would work:

 

very interesting, may have to see if it works just for the hell of it.

 

Codes p1136 p1138 and p455 are gone.

Most solutions point to a bad MAF or a vacuum leak, but I replaced the following:

+ Fuel pump
+ EVAP purge sensor

Drove 1000 miles and restarted the motor about a dozen times without a CEL.

Previously, I checked for vac leaks and replaced the MAF, the fuel pressure regulator, and the fuel filter to no avail (CEL would come on immediately).

One symptom was having a tough time starting the car after a full gas fill up. I believe this was due to the EVAP purge valve sticking open and letting fumes from the carbon canister flood the motor.

The lean codes seem to have been from a failing fuel pump. The pump had 160k miles on it.

I'm wondering how one issue may have created the other.