E-Vap System..

[MSimpson]

Got another SES light today.. 5 one in just 2 months I believe... I asked that guy at AutoZone what the codes were, and he told me that one code read pressure to low twice and another read pressure to high once.. He said more than likely that sensor was bad..

Any input?

[MT-2500]

What were the code no,s?
What year and engine and model?
How many miles?
MT

[MSimpson]

I have 2 codes.. P0453.. P0452.. 4.3 Liter Vortec 2002 Model 100,000 miles..

The SES light has came on and went off 4 times today..Replaced the fuel filter nearly 6 months ago.

Already changed the gas cap..

[MT-2500]

Codes 453 and 452 is low and high voltage from fuel tank pressure sensor.
Can be caused by bad wiring or shorted 5 volt reference feed to it or bad sensor.
If also a code 1635 and 1639 the sensor 5 volt reference voltage is shorted.

Sensor is on top of fuel pump module.
Most of the time the fuel tank has to be dropped to get to or replace it.
Not sure what the sensor cost but you can get the hole module with sensor and fuel pump.
A new AC-Delco/Delphi module cost 250-300 US $
With a 100k on it the pump life is less than half the expected life.
Your choice.
Good luck
MT