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CEL P0174 & P0171

  • Thread starter Thread starter merc123
  • Start date Start date Jul 15, 2006

merc123

Active Member
Jan 27, 2003
420
2
39
North GA
Jul 15, 2006
#1
  • Jul 15, 2006
  • #1
I've recently pulled these two codes

P0174 - Bank 2 too lean
P0171 - Bank 1 too lean

I recently installed a CAI and I'm going to check for any vaccum hoses that may have come off. In addition, I know I have an exhaust leak on my passenger side pipe between my O/R H and the mufflers.

Is it possible my MIL elims could have went bad or just my front O2 sensors going out?

Other than the exhaust leak, O2 sensors or vaccum leak is there anything else I should check while I'm there?
 

sgarlic

Founding Member
Apr 21, 2001
3,085
1
56
Jul 16, 2006
#2
  • Jul 16, 2006
  • #2
O2 sensors don't just go out suddenly, unless you mess with the wiring, cause damage to the sensors themselves, or do something like run leaded fuel.

I would clean the MAF first.. and if that doesn't solve it, fix your exhaust leaks.
 

merc123

Active Member
Jan 27, 2003
420
2
39
North GA
Jul 16, 2006
#3
  • Jul 16, 2006
  • #3
I'm thinking my MIL elims may have gotten water in them and friend them. It was raining pretty heavy and the streets flooded where I was at.
 

Mike97gt

it doe snot
Founding Member
Jan 26, 1999
10,633
7
89
the people's republic of massachusetts
Jul 16, 2006
#4
  • Jul 16, 2006
  • #4
Any vacumm leak can cause these codes. A exhaust leak on both exhaust manifolds ( unlikely) can cause this. or a bad maf

Since you just did a CAI I would start by looking there.

BTW MIL elims have nothing to do with these codes. These are codes related to the fuel table correction, and the rear 02's have nothing to do with that
 

d98gt

Founding Member
Mar 14, 2002
4,505
59
204
SE Texas
Jul 16, 2006
#5
  • Jul 16, 2006
  • #5
There has been 3 posts about the same codes in 2 days I threw the same codes the other day and my little thread shows what my problem was. http://forums.stangnet.com/showthread.php?t=648725

I was lucky enough to have a 51 cent fix
 

merc123

Active Member
Jan 27, 2003
420
2
39
North GA
Jul 18, 2006
#6
  • Jul 18, 2006
  • #6
My CAI pipe had a 1/8" space between it and the TB at the top. I reconnected it and retightened the clamps. If it comes off again, I guess I'll need new clamps

So far no more CEL.
 

Mike97gt

it doe snot
Founding Member
Jan 26, 1999
10,633
7
89
the people's republic of massachusetts
Jul 18, 2006
#7
  • Jul 18, 2006
  • #7
merc123 said:
My CAI pipe had a 1/8" space between it and the TB at the top. I reconnected it and retightened the clamps. If it comes off again, I guess I'll need new clamps

So far no more CEL.
Click to expand...


that would cause it. Glad you found it.
 

d98gt

Founding Member
Mar 14, 2002
4,505
59
204
SE Texas
Jul 18, 2006
#8
  • Jul 18, 2006
  • #8
Gotta love the free/cheap repairs
 

merc123

Active Member
Jan 27, 2003
420
2
39
North GA
Jul 18, 2006
#9
  • Jul 18, 2006
  • #9
They are the best! I just dropped $4500 into my racing engine...shoulda just went 383 blown stroker too bad jail doesn't sound too good to me.
 
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