So I got my service engine soon light checked an this is what I got:

P0411 Secondary Air Injection Incorrect Upstream Flow Detected
P0455 Evap Emission System Leak Detected (Gross Leak/No Flow)

Pep Boys said that the 455 could be causing the 411

I was wondering if just from the codes someone could tell me how much it would cost to fix in an estimate.

What parts, etc...

Thanks

 

Code P0411:

Possible causes:

Defective AIR Diverter Solenoid
Defective Secondary Air Injection (SAI) Pump
Defective Secondary Air Injection (SAI) Pump Relay
Leaking Vacuum Line

Tests/Prosedures:

1. Ground the White/Orange (WT/OG) wire at pin 70 at the Powertrain Control Module (PCM) with the key on and see if the air pump relay and air pump operates.

2. If the air pump does not run, check for battery voltage at the White wire at pin 5 (with pin 70 still grounded).

3. If voltage is present, access the air pump in the front corner of the Right Front (RF) fender and see if battery voltage is present at the pump on the White wire (with pin 70 grounded at the PCM).

4. If voltage is present at the pump, verify the ground circuit (Black wire) is in good condition.

5. If the power and ground circuits are OK, but the pump does not run, replace the pump.

6. If the pump runs after pin 70 is grounded at the PCM, start the engine. Monitor both upstream O2 sensors after grounding pin 70. The O2 sensors should indicate a lean signal immediately.

7. If they do not, then check the operation of the diverter valves and solenoids. Also check for signs of a damaged vacuum line to the solenoid.

Code P0455:

Possible Causes:

Leaking Canister Purge Valve — This valve may leak externally, or it may not open enough to send vacuum back to the fuel tank.
Leaking Canister Vent Control (CVC) Valve — The valve may be leaking externally or it may not close all the way.
Open Evaporative Control Circuit
Leaking Fuel Cap
Leaking Fuel Filler Neck
Leaking Fuel Pump O-Ring
Leaking Fuel Tank
Defective Fuel Tank Pressure (FTP) Sensor

Tests/Procedures:

1. This code suggests there is a leak in the evaporative emissions system.

2. Access the fuel tank pressure sensor voltage with a scan tool. Remove the fuel cap. The voltage should read 2.6 volts with key on engine off, if it does not, suspect blockage in system or failed fuel tank pressure sensor.

3. If the voltage is correct, reinstall fuel cap, now access the canister vent solenoid at the evaporative emissions canister, and the canister purge valve (sometimes referred to as a management valve), it will be located in the engine compartment and will usually have a green cap over its test port. Note at both valves, one wire will have power when the key is on, the other wire will only have ground when the PCM provides it. Backprobe a ground wire into both grounds at both valves.

4. Now start the engine, the vapor management valve should now be putting vacuum to the fuel tank, and the canister purge valve should be keeping that vacuum from bleeding off. You should see the fuel tank pressure sensor dropping its voltage. It needs to be able to drop below .8 volts, if not, there is a large leak. Once it drops below .8 volts, remove the ground wire you applied to the purge valve, now watch the fuel tank pressure sensor voltage for 1 minute. If it bleeds off more than .4 volts, there is a small leak in the system.

5. If you verify there is a leak in the system, block off the canister vent valve, rerun test, if it now passes (can hold the voltage at 1.2 volts for at least a minute), check power and ground to the canister vent valve before replacing valve.

6. If it still fails test, begin blocking off one hose at a time coming from the fuel tank until it can hold vacuum. If it still will not hold vacuum, a smoke machine should be used, look for smoke coming from the tank seams, fuel filler neck, gas cap, fuel pump seal, or other attachments to the tank.

7. This diagnostic will be relevant to most Ford vehicles with evaporative emissions leaks.

99% of the time a gas cap not being put back on all the way or a bad gas cap seal is what causes an evap code to set. I would rule this out before doing anything else.

 

Thanks man. How can I tell if my gas cap seal is bad?

 

Hi,

Just look at the rubber o-ring on the gas cap to make sure its not dry and brittle.

 

Ok its not the O-ring it looks fine, Ill probably go smog it cause they give a free re-test and see what they say, I'll probably ask them to check the gas cap pressure. Any easy inspection I can do, like visually for a leak or something somewhere? Where would I do that, I don't have access to the tools the procedures call for. I do have basic tools and can get under my car. But where should I look?