Tighten Fuel Cap Message

[Topman]

I have 2005 GMC YUKON. Every time I pump gas in it the fuel pump cuts off like the gas tank is full but it’s not full. I change the charcoal canister vent valve solenoid and the purge valve solenoid. Can somebody explain to me why it does that. Then also saids message tighten fuel cap and I replaced it also. I need it fix ASAP can someone help me out?

[Topman]

Anyone have and idea

[Topman]

On 11/13/2019 at 4:41 PM, Topman said:

I have 2005 GMC YUKON. Every time I pump gas in it the fuel pump cuts off like the gas tank is full but it’s not full. I change the charcoal canister vent valve solenoid and the purge valve solenoid. Can somebody explain to me why it does that. Then also saids message tighten fuel cap and I replaced it also. I need it fix ASAP can someone help me out?

 

[newdude]

There is probably a code.  Scan and smoke test it.  Really the only way to properly diag an EVAP issue.  Throwing parts = $$$$$

 

 

 

 

[Topman]

Ok thanks!