Need help with po452 code on ls1 conversion
 

I brought my handy DTC scanner home from work today just to see how many codes my unfinished conversion had set off. I have had trouble with the MAF so I have it unplugged. The truck runs really good and starts really good even with it unplugged. I have another one to install but just hadnt had the time yet.

The only codes that came up were PO102 (MAF sensor) code which I deleted and a PO452 code which says EVAP Emission Control System Pressure Sensor Low. I deleted all of the codes but the PO452 code stayed on the scanner. It would not let me delete it. I did this a few times and it never would go away. I am thinking this is what they call a "hard code"??

I started the truck up for a few minutes and then checked the codes again to find of course the PO102 again and the PO452 was still there.

I have had all of the emission pieces removed. The fuel sending unit and fuel pump have no emission related pieces on them at all. Is this just something that my programmer didnt take off or something?

Here's what somebody wrote about the code on another post:
"PO452 indicates high pressure in the fuel tank (low voltage= high pressure, high voltage= low pressure) which could mean a crimped evap line or fuel line. I would also check the fuel rail pressure with a gauge. Are you getting a TPS code?"
I havent checked the pressure at the rail and I dont get that code.

Thanks for any help that you guys give!

-Aaron

I have the same problem on 2001 Z28 and it smells like fuel.