Hi,

I have a problem with the evap emissions control system but I don't know where I should start. I would appreciate any adivce on things to test. The check engine light was going on and off, but now it hsa been on for awhile. The most recent code is:

P0452 - Evaporative Emissions Control System Pressure Sensor Low Input

Perviously it has stored these two codes (taken about 2 weeks earlier):

P0446 Evaporative Emission Control System Vent Control Circuit Malfunction
P0453 Evaporative Emission Control System Pressure Sensor High Input

Thanks,Vince

 

Doubble check the gas cap, it's the easiest way to go. Unless you take it somewhere to get it smoke tested, you can't really find the leak yourself.

 

Vince,
With those codes I would suspect a faulty fuel tank pressure sensor with about 99.9% certainty.

 

ZX110F1,

I had the fuel pump and tank replaced about a year ago. Is the fuel pressure sensor part of the pump/sending unit?

 

It is attached to the sender assembly but it is a separate serviceable item.Aka: Fuel Vapor Pressure Sensor.

 

Is there anyway to test the sensor before replacing it? I phoned the local chev dealer's parts department and they told me that the sensor was a part of the fuel send unit and was not serviceable, are they pulling my chain? I have a Chev 1998 C/K Sierra with a 4.3l v6 engine.

 

The sensor is part of the sending unit, but itis not in the tank. It's located on top of the fuel pump module and has a wiring connector . Look on eBay at auction 8043135302. I think this is the correct sensor for your vehicle.

 

Ron,
That's the ticket, good find.