B.Eddy

Have a 99 with 5.3 and have check engine lights that wont go off and wont stay off when I clear them.

P1404- EGR valve closed pintle position
P0453- Fuel tank pressure sensor circuit-high voltage
P0446- EVAP vent system performance

Guy I got the truck from told me that it had already been checked and it was the EGR valve. Replace it ($125)......nope not it. Cleaned the egr pipe......nope not it. Been told that the pressure sensor on the gas tank go bad and that GM has even redesigned the sensor but I wanted some input before going and buying another part that isnt needed.

I did notice that as I was driving the other day without the radio on the when I began pulling a little hill and kinda bogging it the engine began the little timing ticking thing like it had bad fuel. Other than that the engine runs, idles, and pulls very good.

I replaced the EGR valve and cleared the codes and within about 45 seconds the light came back on. Went home and cleared them again and within about 3 miles light came back on. I put about 200 or so miles on the new valve now and still no luck going off.

Any help and suggestions would be great. If you have a smartass comment you can keep it to yourself as well. Im looking for help not a smartass who has to boost their ego about themselves by calling somebody else out on thier lack of experience on this engine. Thanks in advance.