Ok, so over it! My 98 5.4 Triton (114,000) girl is giving me trouble. It all started with all the Emission codes – replaced everything, 02 sensors, DPFE, EGR, Vent Canister, Vapor Canister (which was completely melted, I believe from a exhaust leak) cleaned the MAF and a Seafoam treatment for safe measure, replaced numerous hoses. I now have a Freeze Frame code with a excessive leak! She is running rough, almost like chugging and starving for gas! I can not hear a vacuum leak anywhere basically all the hoses under the carriage have been replaced with the exception of dropping the gas tank to get to that hose!! Please dear god someone point me in the right direction if you can

 

You need to post the exact numerical "P" code, please.

 

Thanks glc for taking the time to read my thread! I, of course forgot the paper on the counter at home. I was just going off memory from what I could remember. I wanna say it was P0455. I have also replaced the gas cap and when I was under the truck replacing hoses near the rear tires I could smell gas.

 

Technical Description

Evaporative Emission Control System Leak Detected (no purge flow or large leak)

What does that mean?

This indicates a fuel vapor leak or lack of purge flow in the EVAP control system. It means a large leak has been detected. The (EVAP) emission control system prevents the escape of fuel vapors from a vehicle's fuel system. Fuel vapors are routed by hoses to a charcoal canister for storage. Later, when the engine is running a purge control valve opens allowing intake vacuum to siphon the fuel vapors into the engine.

Symptoms

You likely won't notice any drivability problems.

Causes

A code p0455 most likely means one or more of the following has happened:

A loose or improperly affixed gas cap
A non-conforming gas cap (i.e. not factory/original brand)
Other leak or damaged piece in EVAP system

Possible Solutions

With a p0455, the most common repair is to:

Remove and reinstall the gas cap, clear the codes, and drive for a day and see if the codes come back.
Otherwise, replace the gas cap, and/or
Inspect the EVAP system for cuts/holes in tubes/hoses (you may hear a vacuum noise or smell fuel), repair if necessary

Read more at: http://www.obd-codes.com/p0455
Copyright © OBD-Codes.com

I see a gas tank drop in your future.

 

Here's a Diag or what it all looks like, just drew it my self , -

 

Look at UR fill neck.
Dorman Fuel Filler Neck .
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You need to start with the accurate code and not a guess.
Good luck.

 

OEM gas cap is the only one rated for your vehicle.


Check under the bed on the left front corner of the bed, the filler neck also has a vent hose running along side of it. Both should be in good shape.

You can have the system smoke tested at a shop to pinpoint the leak and quit throwing parts at it.

Good luck
-Patrick