P0174

LaserSVT

Got FB banned again for saying nards
Founding Member
Nov 29, 1999
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I know this code is for bank 2 lean condition.
I only get the code at idle or just off idle with low-no load. I have a new IAC and MAF. The t-body is clean and there are no vaccume leaks anywhere. The only place I couldnt check was the evap system. The fuel filter and pump are new as well.

So what does that leave? The O2 sensors? Would it be the front one or the rear that just makes sure the front one is working?

Thanks for any input guys.
BTW, this is my 97 Mark VIII I am referring too :nice:
 
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I know this code is for bank 2 lean condition.
I only get the code at idle or just off idle with low-no load. I have a new IAC and MAF. The t-body is clean and there are no vaccume leaks anywhere. The only place I couldnt check was the evap system. The fuel filter and pump are new as well.

So what does that leave? The O2 sensors? Would it be the front one or the rear that just makes sure the front one is working?

Thanks for any input guys.
BTW, this is my 97 Mark VIII I am referring too :nice:

if its just one bank , could be bad o2 , or intake gasket leaking air in between in the intake and head on that bank
 
if its just one bank , could be bad o2 , or intake gasket leaking air in between in the intake and head on that bank
Checked that thuroghly. Used a whole can of starting spray testing every gasket and vaccume hose on the car :nice:

O2s are stock still yet. Does the stuff I am getting from you allow me to turn off the rear O2 sensors?
 
if you have a leak before the front 02 sensor it will throw that code
No leaks. As stated earlier, I have tested the whole vaccume system and lenum gaskets. The car is whisper quiet with no exhaust noises so i know my exhaust is not leaking. My cats prolly need to be replaced cause when i really get on it, it makes a rotten egg smell indicative of old cats :shrug:
 
Take this with a grain of salt when reading.... I had this code along with I THINK 0420 or 0421 and it was the Evap Canister Purge Valve in the passenger front wheel well under the plastic panels. I swapped the purge valve ($34 on rockauto dot come) and the upstream o2 sensors ($32/ea on rockauto) and problem solved. Hope you get it fixed!
 
Yeah, i am leaning twords it being O2s. I just dont know if its the front or rear ones.
get code P0174 pretty regularly (Bank 2 lean) and twice I have gotten p0171 (bank 1 lean)

When my Sniper software gets here i am gonna disable the rear O2s and see if the code comes back. If it does then I will know its the front ones.
I had suspected the evap system as the code only appears at idle which would indicate a vac leak and since I couldnt find one then that would point to the cannister ;shrug:
 
I'd guess it's your o2 sensor throwing the error. With the car being 11 years old, those o2 sensors go pretty quickly. My GF's 97 Ranger just threw that code about 3 weeks ago, tossed on a new o2 sensor, cleaned the MAF... problem solved.

New o2's go for about 85 bucks, give or take a few.
 
Fwiw . Helped a fellow stangnet member last week with same codes .he had a cai that was not installed right. Eighter the filter was not on tube right or if tube can go into maf that side. He said filter . I dont have one so im not sure how ht goes together. He also had a broken clip on maf so plug could have been loose?
 
The front o2s are the only ones that tell the computer any real useful info about air fuel ratio. The rears are only on there to tell if the cats are doing their job. I'd bet it's that o2 going south.