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  • 1996 - 2004 SN95 Mustang -General/Talk-
  • SN95 4.6L Mustang Tech

DTC p1151 and p0420

  • Thread starter Thread starter zeevann
  • Start date Start date Nov 19, 2008
Z

zeevann

Member
Apr 15, 2007
55
0
6
Nov 19, 2008
#1
  • Nov 19, 2008
  • #1
i would like to know what your opinions are on these codes. Its on my 99 cougar, IK IK its not a mustang but stangnet has always been the most helpful. Thanks for any help :SNSign:
 

hotcobra03

Active Member
Nov 29, 1999
969
4
39
poteet,tx
Nov 19, 2008
#2
  • Nov 19, 2008
  • #2
Driverside front o2 and cat .when was last full tune up? Change all o2s.best i got
 
Z

zeevann

Member
Apr 15, 2007
55
0
6
Nov 19, 2008
#3
  • Nov 19, 2008
  • #3
last winter i did the tune up on it. i just changed oil and air filter like 2 weeks ago.
 

hotcobra03

Active Member
Nov 29, 1999
969
4
39
poteet,tx
Nov 19, 2008
#4
  • Nov 19, 2008
  • #4
Tell alittle more history.yr?engine size?you live up north?
 
Z

zeevann

Member
Apr 15, 2007
55
0
6
Nov 19, 2008
#5
  • Nov 19, 2008
  • #5
alright its a 99 cougar. 2.5 v6. yes i live in upstate new york. umm i changed one o2 sensor and it went off for quite come time 2 weeks. then poof cel. the thing that sucks is that its my winter car i need it inspected by the end of the month
 

hotcobra03

Active Member
Nov 29, 1999
969
4
39
poteet,tx
Nov 19, 2008
#6
  • Nov 19, 2008
  • #6
Your car sounds like it sits a lot. If you can change plugs ,pcv ect....your o2s control fuel and 1151 is your o2 on than off on off, switching like a carb had screws to adjust o2s are the screws.try 93 or 94 not sure if they use that winter blend anymore .start their.autozone bosch o2s are around 50 each .
 
S

SilverBullet00

New Member
Jul 5, 2004
1,150
0
0
Wichita, KS
Nov 20, 2008
#7
  • Nov 20, 2008
  • #7
Those cars are known for electrical gremlins. I had a friend with a 99, it was a nightmare...

Your cat could be clogged or damaged as well. did you replace the 02 sensor with an ford motorcraft part?
 
Z

zeevann

Member
Apr 15, 2007
55
0
6
Nov 20, 2008
#8
  • Nov 20, 2008
  • #8
i bought a Bosch one
 
Z

zeevann

Member
Apr 15, 2007
55
0
6
Nov 20, 2008
#9
  • Nov 20, 2008
  • #9
both rear o2's are replaced now and p0420 is still coming on
 
Z

zeevann

Member
Apr 15, 2007
55
0
6
Nov 21, 2008
#10
  • Nov 21, 2008
  • #10
well it turns out my old cougar just needed an update from ford to fix the problem.
 

hotcobra03

Active Member
Nov 29, 1999
969
4
39
poteet,tx
Nov 22, 2008
#11
  • Nov 22, 2008
  • #11
What was the update? Glad to hear its ok now
 
P

poindexternasty

New Member
Apr 29, 2008
148
0
0
Nov 22, 2008
#12
  • Nov 22, 2008
  • #12
My 02 threw a code like that.... not sure... might have been 0421 or 0420, i dont remember. Anyway, the problem ended up being the vapor cannister purge valve. Hope it helps.
 
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