Mustang_Matt01

Hey all,
I've got a 2001 GT which recently tripped a check engine light. Pulling the codes initially I had P0455. I did some basic checking and figured I'd be better off taking it in to a dealer with a smoke machine so they can find the leak. And by the time I got it to the dealership it was also tripping a P0401. The dealership replaced the DPFE sensor and the hoses running to it. I thought this was suspicious, but the very next day my car trips another check engine light. This time it has P0456 and P0457. And now they claim to have found a leaky seal in the fuel fill up neck.

My thought is that this leak was there all along, and it caused all of these fault codes to set (just depending on level of fuel and what rpms the engine was running when the PCM noticed a problem). And I think they should reimburse me for the DPFE sensor that the technician swapped before he did a complete check.

Just wondering if anyone else has ran into this or can convince me that a leak in the EVAP system can in no way impact the EGR system (as far as I know they use the same vacuum lines and they both go into the intake, so an air leak should impact both).

Thanks in advance!

duely4991

hey just a quick toss up for anyone trying to find where the "small leak" from the error code P0456, recently i have been troubled in finding the cause of the problem i suggest that anyone who has this issue go get a smoke evap test done the leak will be small but very complicated to find! but that is a given.... my problem believe it or not was due to speed bumbs! i would bottom out on speed bumps and my exhaust tail pipes would be pushed up far enough to touch the evap lines that are next to the mufflers. come to find out its not a rubber hose under there its a plastic line wraped in a heat shield but if the exhaust pipe touches it its melts!!!!!! causing a hole there is a 3 leaf clip that holds these vapor lines in place and due to fords amazing design cough cough!! there deadly close to the exhaust pipes. now befour anyone says ohh why did you go so fast over them, i in fact did not! the rear suspension will still allow the car to drop down a few inches given the speed bump is a abnormally large one

so lesson here is avoid speed bumbs if possible!!! and check the evap lines closest to the exhaust

hope this may of been helpful for troubleshooting and avoiding future evap problems