Has anyone gotten a Code P0456

[Kevinmach1]

Has anyone gotten this code P0456? < Its says emission evaporator system leak (small leak detected).

What does it mean? What's leaking?

 

[Aandf1978]

Might be helpful...

Causes


Usually this P0456 code is caused by an incorrect or faulty gas cap. Filling the fuel tank with the engine running could conceivable cause this code as well or if the cap wasn't properly tightened. Any of the following could also be the cause:

• A small leak in any of the EVAP hoses or fuel tank hoses
• A small leak in the purge valve or vent valve
• The EVAP Canister may be leaking

Possible Solutions

First, using a scan tool activate the vent solenoid, sealing the system. Then monitor the fuel tank pressure (FTP) sensor. If the system is sealing properly, the number will stay consistent. If is isn't, the pressure sensor will show that as well. If the system slowly leaks, use a smoke machine and watch for smoke exiting the system at any EVAP component. Any where there is smoke exiting the system, that is the faulty component. Do not pressurize the EVAP system with air pressure. Doing so can damage the purge and vent solenoids in the system.

 

[tmcolegr]

there is a TSB on this issue. PM me with your email address and I'll send you a copy

 

[mikeysgt]

Bump. Just got this code. Can it be caused by not tightening the oxygen sensor enough and it causing a leak? (front driver side).

I pulled my longtubes and put my stock manifolds back on over the weekend. I forgot to put the o2 sensor on the driver side one before putting the manifold on the block. Only way I could reach from the bottom was enough to barely hand tighten the sensor.


Also, could a leak in the connection between the stock manifolds and midpipe cause it as well? I couldn't find my damn stock nuts that go on the exhaust manifold studs so had to go buy regular nuts at lowes to hold it together until I went to ford and bought the stock nuts (which I think are locking) just now after work.

 

[AbdullaGT500]

Gas cap! Tighten the gas cap and clear the code and see if it comes back first.

 

[Ryan331]

Bump. Just got this code. Can it be caused by not tightening the oxygen sensor enough and it causing a leak? (front driver side).

I pulled my longtubes and put my stock manifolds back on over the weekend. I forgot to put the o2 sensor on the driver side one before putting the manifold on the block. Only way I could reach from the bottom was enough to barely hand tighten the sensor.


Also, could a leak in the connection between the stock manifolds and midpipe cause it as well? I couldn't find my damn stock nuts that go on the exhaust manifold studs so had to go buy regular nuts at lowes to hold it together until I went to ford and bought the stock nuts (which I think are locking) just now after work.

Where did you lift/support the car? any damage to the EVAP lines (a small crack/etc) can set this code..

 

[mikeysgt]

Block of wood between the jack and under the crank area on front of the block. I'll check the gas cap first but haven't had that happen in the 5 years I've had the car

 

[Alfiedagr8]

Your gonna have to
Smoke test the evap system to find the issue.
Also look at the grommet on filler cap see if it's cracking. Check your evap canister for cracks. If it's all
Good. Smoke test. Did you mess with the fuel system at all?

 

[mikeysgt]

Haven't touched the fuel system at all. I'll check the cap and see if there's anything wrong with it. Where do I get it smoke tested in case I have to? And rough estimate on how much it costs?

 

[Alfiedagr8]

Any dealer should have the tool. Also some independent shops may have it too just be sure to ask. But I recommend a dealership since we have the IDS tool to electronically shut the CVV. This is better then pinching the line since I have seen the CVV not fully shut sometimes causing this code. They should charge you only 1 hr. About 100 bucks. If they ask for more then they are Thieves. I only charge one hr for complete diagnostics. Good luck.

 

[Ryan331]

Haven't touched the fuel system at all. I'll check the cap and see if there's anything wrong with it. Where do I get it smoke tested in case I have to? And rough estimate on how much it costs?

Any chance you contacted/unsettled the line or any connections near the headers/under the hood? esp if you jacked up the engine, may have crushed something against the bulkhead

 

[mikeysgt]

Which line is it specifically? I'll check it tomorrow morning when I get the car on jackstands

 

[shikwann]

I had the same problem and I fixed it, one of the hoses was unplugged on the drivers side on the black blob thing, check there

 

[mikeysgt]

I had the same problem and I fixed it, one of the hoses was unplugged on the drivers side on the black blob thing, check there

Can you get me a pic of what hose you had unplugged? really don't want to have to take a trip to the dealership if I don't have to

 

[mikeysgt]

Just got up and started with trying to find the problem. Checked fuel cap first and I think that may have been the culprit. Didn't seem like it was on securely and seemed a little easy taking it off. I'm putting the car up on stands and going to do a visual check on the lines just to see if I see anything wrong. I'll clear the code and see if it comes back on in the next couple days

 

[Kevinmach1]

Mine was the gas cap...

 

[mikeysgt]

got the car up and checked all the lines and couldn't detect anything wrong on them. I managed to slide the o2 sensor socket in through the back of the motor to tighten the front driver side one that was loose also. Cleared the code and hoping it won't come back again in a couple of days. I drove the car from the end of the longtube removal about 35 miles round trip for 6 days before that code came on. I did put some gas in the car on thursday night so maybe that caused the code to come on on friday. i figure if it was something else, shouldn't the code have come on soon than friday?

 

[tmcolegr]

What year vehicle?

 

[mikeysgt]

2006

 

[tmcolegr]

Tsb 07-3-9 mil on - dtc p0456

FORD:
2005-2006 Mustang

ISSUE:

Some 2005-2006 Mustang vehicles may have a malfunction indicator lamp (MIL) on with diagnostic trouble code (DTC) P0456. This concern can be caused by an oversized orifice in the fuel pump. Suspect fuel pumps are in vehicles built before January 1, 2006.
ACTION:

Follow the Service Procedure steps to correct the condition.
SERVICE PROCEDURE

Install the scan tool on the vehicle and monitor various inputs at different conditions to see if the vehicle needs to have the fuel pump replaced based on the calculation.

Mustang Vapor Generation Test



NOTE:VEHICLE MUST MEET THE FOLLOWING CONDITIONS FOR THIS TEST: FLI% BETWEEN 15%-50% (INDICATES RIGHT SIDE FUEL TANK IS EMPTY) AND FUEL/VEHICLE TEMPS BETWEEN 70-80 °F (21-27 °C).

1. Install IDS and perform Data logger function.
2. Select the following PIDs: FLI% (fuel level), FRP (fuel rail pressure), VMV# (Vapor Management Valve current), FTP voltage (Fuel tank pressure transducer output voltage), CVV# (Canister vent valve duty cycle).
3. Start engine - run for 5 minutes - turn off engine.
4. Access Jet Pump Module Connector 434 and verify sender resistance is at empty (16 ohms ± 1 ohm).
5. Start engine, let idle for 30 seconds.
6. Check FRP to ensure fuel pressure is at 40 PSI ± 2 PSI.
7. Close VMV to ensure a purge cycle does not take place during testing.
8. Record FTP voltage (should be at atmosphere - 2.61 volts).
9. Close CVV and monitor the elapse time.
10. Record FTP voltage after 30 seconds.
11. Open CVV and turn off engine.
12. Record FTP voltage (should be the same - 2.61 volts).
13. Close CVV and monitor the elapse time.
14. Record FTP voltage after 30 seconds - open CVV. Calculate Dynamic vs. static FTP rise
15. Take reading from Step 10 (should be near 2.61) and subtract by the value in Step 8.
16. Take reading from Step 14 and subtract it by the reading in Step 12.
17. Take number from Step 16 and divide it by the number in Step 15. If the calculation is greater than a factor 3, replace the fuel pump. If the calculation is less than 3, continue with Worshop Manual diagnostics.
18. If the results from the dynamic test (KOER) are 3 times larger as the results of the static test (KOEO), the fuel pump is generating excess vapor.

PART NUMBER PART NAME
7R3Z-9H307-C Sender Asy - Fuel Tank