Changed fuel lines now get 452 code?

 

Here's the flow chart for P0452, follow it and you'll find the problem:
https://blazerforum.com/forum/diagno...plained-35142/

 

When i open the gas cap i dont hear any air escapeing like i use to.I didnt fill the gas tank when i put it back in only about 5 gals would that make adifference ? i checked all tcnnections all seems right .doesthat code 452 mean its only electricical?

 

With this EVAP system, you should never hear pressure or vacuum when removing the fuel filler cap. The DTC is indicating a problem with the fuel tank pressure sensor or its circuits.

 

Thanks Capt Hook Took off connector & cleaned it re connected & light went out i hope it stays out .Thanks again for setting me straight... Jim

 

You're welcome, glad you got her fixed. Thanks for posting back!

 

I'm sorry to bring back an old thread but I'm having p0452 issues and i was looking around it looks like the metal line from the tank up to the engine is leaking would that be able to cause a p0452? its confusing because its only an issue in the morning time/not up to operating temp. either way obviously i gotta fix it but I'm hoping i can stop racking my brain over this now.

thanks in advance

 

P0452 is an EVAP DTC indicating there is a fault in the fuel tank pressure sensor, (located on top of the fuel tank) or its circuits. If the steel line is 3/8", (fuel pressure) or 5/16", (fuel return) it will leak liquid fuel when the engine is running, it will not set any DTC's. If the leaky line is 1/4", it is the vapor line for the EVAP system and will only leak fuel vapor, (or vacuum while the system is testing or purging). A leak in this line will cause P0440 and or P0442.