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

Help! P1151 engine code???

  • Thread starter Thread starter 98BLKHRSE
  • Start date Start date Mar 1, 2004
9

98BLKHRSE

New Member
Nov 30, 2003
40
0
0
Rochester, New York
Mar 1, 2004
#1
  • Mar 1, 2004
  • #1
Well it has finally been nice enough around here (new york) to get my car out since its been stored 5 months ago. Late last fall i put on a new UPR x-pipe. I love the sound and the new power. I also installed a set of "plug and play" mil eliminators at the same time. Ever since then, the car has been running really rough. I mean to the point where the whole car bucks EXTREMELY hard throughout the rpm's especially above 3K. And ofcourse the engine light has been on despite the mil elim's continuously.
Well after 5 months of sitting the car is just the way i left it. (not like i thought it was gonna change any) I took it to auto zone today to have the codes pulled and a "P1151" is what they told me. The guy said it is some air/fuel monitoring malfunction code. Any ideas as to what that code really means and how to fix it would be greatly appreciated. Thankz guys!!
 
R

Rev Maynard

New Member
Dec 2, 2003
29
0
0
PA
Mar 1, 2004
#2
  • Mar 1, 2004
  • #2
I don't know if it'll help but.. http://www.bullittarchive.com/reference/DTC/
might get you in the right direction as far as the code(s)and the "what do I check next" stuff.
Prob a leak or something with the CAI/MAF if I had to guess
 
9

98BLKHRSE

New Member
Nov 30, 2003
40
0
0
Rochester, New York
Mar 1, 2004
#3
  • Mar 1, 2004
  • #3
anybody else ever heard of this code?
 

MT1083

New Member
Sep 16, 2003
1,033
0
0
Charlotte, NC
Mar 1, 2004
#4
  • Mar 1, 2004
  • #4
The official definition that I have for it is - "H02S BANK 2 SEN 1 INSUFFICIENT SWITCHING LEAN MEAN". I'll look it up further when I get home and see if I can find some troubleshooting info.
 

MT1083

New Member
Sep 16, 2003
1,033
0
0
Charlotte, NC
Mar 1, 2004
#5
  • Mar 1, 2004
  • #5
Okay here is the description in my manual..."A HEGO sensor indicating lean at the end of a test is trying to correct for an over-rich condition. The test fails when fuel control system no longer detects switching for a calibrated amount of time."
List of possible causes:
excessive fuel pressure, leaking/contaminated injectors, leaking fuel pressure regulator, low fuel pressure or running out of fuel, air leaks after the MAF, Vacuum leaks, PCV system, improperly seated oil dipstick, leaking EGR gasket, stuck EGR valve, leaking diaphragm or EVR, Oil overfill, Exhaust leaks before or near the heated 02 sensors.

Hope this may help!
 
9

98BLKHRSE

New Member
Nov 30, 2003
40
0
0
Rochester, New York
Mar 1, 2004
#6
  • Mar 1, 2004
  • #6
do you think the rough bucking is from a rich condition, or something else?
ive already changed the plugs, wires and fuel filter.
 

MT1083

New Member
Sep 16, 2003
1,033
0
0
Charlotte, NC
Mar 1, 2004
#7
  • Mar 1, 2004
  • #7
I really don't know. I've just picked up all of my extremely limited knowledge from these guys here on stangnet. Hopefully they can help since I had that manual info.
 

mogs01gt

Founding Member
Jul 22, 2002
3,113
30
119
Ohio
Mar 1, 2004
#8
  • Mar 1, 2004
  • #8
I think it is the MILs. Unhook them and leave them off. Hook the o2 sensors back up. Unplug the negative terminal for 10 minutes, attach it back on. Take if for a spin for a little and see if it continues.
 
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