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  • SN95 4.6L Mustang Tech

EXHAUST LEAK FIXED NOW P0455 & P0401

  • Thread starter Thread starter rispoli_23
  • Start date Start date May 29, 2010

rispoli_23

Member
Jul 7, 2008
182
0
16
May 29, 2010
#1
  • May 29, 2010
  • #1
MORE PROBLEMS MORE MONEY ..... ok everyone knows about my idle problems well i find out my exhaust was leaking where the h pipe and manifold connects on the passanger side so i get it fixed now im getting codes p0455 and p0401 i swear i cant win ...
 

wmburns

SN Certified Technician
Aug 14, 2009
5,892
514
204
Houston Texas
May 29, 2010
#2
  • May 29, 2010
  • #2
Check Fuse F2.8

OK, I am going out on a limb here. New problem in the EGR system and EVAP system started at the same time. What do the two systems have in common? How about fuse F2.8 in the Central Junction Box?

>>>From Ford service CD
P0455 - EVAP Control System Leak Detected (No Purge Flow or Large Leak) The PCM monitors the complete EVAP control system for no purge flow, the presence of a large fuel vapor leak or multiple small fuel vapor leaks. The system failure occurs when no purge flow (attributed to fuel vapor blockages or restrictions), a large fuel vapor leak or multiple fuel vapor leaks are detected by the EVAP running loss monitor test with the engine running (but not at idle).

  • After-market EVAP hardware (such as fuel filler cap) non-conforming to required specifications
  • Disconnected or cracked fuel EVAP canister tube, EVAP canister purge outlet tube or EVAP return tube
  • EVAP canister purge valve stuck closed
  • Damaged EVAP canister
  • Damaged or missing fuel filler cap
  • Insufficient fuel filler cap installation
  • Loose fuel vapor hose/tube connections to EVAP system components
  • Blockages or restrictions in fuel vapor hoses/tubes (items also listed under disconnections or cracks)
  • Fuel vapor control valve tube assembly or fuel vapor vent valve assembly blocked
  • Canister vent (CV) solenoid stuck open
  • Mechanically inoperative fuel tank pressure (FTP) sensor
Check for audible vacuum noise or significant fuel odor in the engine compartment or near the EVAP canister and fuel tank.

P0401 - EGR Flow Insufficient Detected The EGR system is monitored during steady state driving conditions while the EGR is commanded on. The test fails when the signal from the DPF EGR sensor indicates that EGR flow is less than the desired minimum.

  • Vacuum supply
  • EGR valve stuck closed
  • EGR valve leaks vacuum
  • EGR flow path restricted
  • EGRVR circuit shorted to PWR
  • VREF open to D.P.F. EGR sensor
  • D.P.F. EGR sensor downstream hose off or plugged
  • EGRVR circuit open to PCM
  • VPWR open to EGRVR solenoid
  • D.P.F. EGR sensor hoses both off
  • D.P.F. EGR sensor hoses reversed
  • Damaged EGR orifice tube
  • Damaged EGRVR solenoid
  • Damaged PCM

Perform KOER self-test and look for DTC P1408 as an indication of a hard fault. If P1408 is not present, look for contamination, restrictions, leaks, and intermittents.
 

rispoli_23

Member
Jul 7, 2008
182
0
16
May 29, 2010
#3
  • May 29, 2010
  • #3
Lol Thanks ill check it
 

rispoli_23

Member
Jul 7, 2008
182
0
16
May 29, 2010
#4
  • May 29, 2010
  • #4
found a vac line that popped off somehow ... hope thats it
 
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