rab538

This is my brand new fault P0455 Severe Purge system leak ... WTF is this ?
help please !!!!

mcphere

Check it out with a fully qualified mechanic.

From my www.alldatadiy.com account and for your information it says...

Major Leak in Purge System :: Hose in System Not Connected or Filler Cap Open (P0455)


Check Component B4/3 (Fuel Tank Pressure Sensor). (Only (USA))

Test 1 Test Component B4/3 (Fuel Tank Pressure Sensor) By Actuation.
Test 2 Test Voltage Supply of Component B4/3 (Fuel Tank Pressure Sensor).

1 Test Component B4/3 (Fuel Tank Pressure Sensor) By Actuation.

Figure legend

* 019 Vacuum tester
* b Purge line from activated charcoal canister to component Y58/1 (Purge control valve)
* Y58/1 (Purge control valve)

Test sequence

* Switch off ignition.
* Detach purge line to activated charcoal filter at component Y58/1 (Purge control valve) and connect vacuum tester to purge line.
* Switch on ignition.
* Actuate component Y58/4 (Activated charcoal canister shut-off valve).(Operate pushbutton F2.)

Note! Communication with ECU required.

** End of Test **

2 Test Voltage Supply of Component B4/3 (Fuel Tank Pressure Sensor).

Test requirement

* The actual value is not o.k.
* The voltage supply of the component N3/10 (ME-SFI control module) is o.k..

Test sequence

* Switch off ignition.
* Connect socket box (35-pin) to component N3/10 (ME-SFI control module).
* Connect socket box (126-pin) to component N3/10 (ME-SFI control module).
* (5.5) Pin 5 of 35 <--> Pin 125 of 126 (4.40)
* Switch on ignition.

Specified value

* Voltage[4.75...5.25] V

Question

* Is the measured value okay? Yes

The measured value is o.k.
Further possible causes of fault

* Inspect cables from component N3/10 (ME-SFI control module) to component B4/3 (Fuel tank pressure sensor).
* B4/3 (Fuel tank pressure sensor)

No
The measured value is not o.k.
Possible cause and remedy

* Inspect cables from component N3/10 (ME-SFI control module) to component B4/3 (Fuel tank pressure sensor).
* N3/10 (ME-SFI control module)

** End of test **

55fanatic

check to see if your gas cap is loose?

jpniner

I have this exact same problem as of today in my 1999 ML 320.....is this a bad problem or another one of these minor annoynces this car tends to have?

today the CEL came on, then after driving for awhile the low fuel thing started flashing(i had a half tank in)

I did get cheap and put the 87 grade in for a half tank last week, not sure if that could have anything to do with it?

jpniner

if its not the gas cap, and its the hose....How hard is that to replace, can it be done by yourself?