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Fuel Check Engine/fuel Cap Light On... 03' Mach 1

  • Thread starter Thread starter trufflebutter
  • Start date Start date Dec 31, 2016
T

trufflebutter

New Member
Apr 16, 2015
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0
1
Dec 31, 2016
#1
  • Dec 31, 2016
  • #1
Hello ladies and gents -

Jump right into it. 2003 Mach 1, 50XXX miles.

Had my fuel pump and filter changed not to long ago since the car decided not to start on me one day and it came to that. Then of course, the Check-Engine-Light came on some days later. Got it checked via auto-zone, came out as a EVAP - gross leak or gas cap. So, took it back to get it checked just-in-case thinking the shop that put in the fuel pump and filter may have missed something. They said all was well and put in a new gas cap while it was there for me. Check light went away.

Light came back again, got it checked once again, yet it went right away when it was being checked. Thinking it was cleared perhaps on accident.

Then, of course, damn light came back. Has been on ever since. Code being, P0455 - EVAP - large leak/gross leak. And now, the Check-Fuel-Cap light is also now on.

So, new cap being in, have tired to tighten it as much as I can without breaking it.. New pump and filter. And yet both lights are still on.

I may go and try to get it cleared if someone can and go some days to see from there. But for both lights to come on now with everything being "new..."

Anyone have a clue to what this all is.....?

Thanks anyone and everyone!
 

trinity_gt

10 Year Member
Jan 31, 2003
3,125
81
99
Canada
Dec 31, 2016
#2
  • Dec 31, 2016
  • #2
Check the grommet/seal where the filler pipe enters the fuel tank.

 
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