code 176 - new o2 sensor - help!

Bacondoggy

Registered User
all new O2 sensors - and I reset the codes - I keep getting code 176

I hear different versions of this code - running lean on driver's side, and o2 sensor not switching... which is it???

What could this be? Injector, or could the engine not be grounded? I know engines usually have a thick braided ground wire going to the engine - I don't remember if I have one on my car (its been YEARS since I had the engine out, and I dunno if I installed it or not). Where on the engine would it be (any pictures would be helpfull)? I don't mind putting a ground on the engine, but usually there is a bolt or something to connect the grounding wire to the block, and I have NO idea where that would be.
 
Not sure what's going on but try looking to see if the ground wire that rests behind one of the heads is properly connected. I think it's the driver head but could be wrong. I had O2 CEL codes come up when I forgot to connect that wire.
 
I can't even see back there... is it best to check from under the car? if its not hooked up, and I don't see a ground wire hanging there, I guess I will ger another one, but where should I run the other end of the wire?
 
I can't even see back there... is it best to check from under the car? if its not hooked up, and I don't see a ground wire hanging there, I guess I will ger another one, but where should I run the other end of the wire?

Well hold on now, the ground wire I'm talking about goes back into a wiring harness.

Don't hook up just any ground wire, you should already have a simple ground from the sub-frame to the block up in front of the car.

The one your looking for is thin and has round connector on the end. You'll need to remove parts to see it I'm sure.
 
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any pictures guys? what harness has the ground wire? I talked to the mechanic alittle bit ago and he said all the ground circuits tested ok, so what about the ground to the block? You said it is in the front - where at?
 
could it be the fuel pressure regulator? A guy a a parts store (who knows nothing about our cars) told me if that is clogged or not working properly, that it could be making the drivers side bank not get enough fuel... in the meantime, I bought a generic engine grounding strap - I will see if this does anything...
 
bump.... anyone here? I still can't find an orange wire here anywhere, I assume the grounding strap will resolve this? Any other problems people have had with their car's drivers side bank running lean and its NOT the O2 sensor???
 
ok I had to dig up this old thread because I am having the same problem - I am getting a lean code for the driver's side bank only - I have a new exhaust system 2.5" dual maganaflow res into a borla resonator and 2.5" the whole way back (all stainless from the resonators back ;)) What can be causing the lean code for only the drivers side bank? I have a new Bosch (from advanced) O2 sensor...
 
lean

Have you checked your fuel pressure lately?lean means not getting enough gas/-fuel filter-fuel pump-fuel pressure regulator.

That orange wire is way in the back by the fire wall it wraps around the back of the harness of the fuel rail right where the fuel pressure regular bolts to the head.It has a gray boot wrapped around it so you wont really see orange and it has a round ring for the bolt to go through it.

Tom
 
haven't checked the pressure latley - a fuel pump and FPR are next on my list... I have heard of people getting FPR's and adjustable ones... what is recommended? What have most people been running in our cars? Would I do better with a new OEM one, or are there better aftermarket options out there? I know my CEL comes on consistantly around the exact same spot when I am driving to work, then stayes on... it seems to be around 10-15 minutes or so. It comes on usually when I am drifting, and not under hard acceleration. I was just thinking - I have a NEW ford O2 in the passenger side, and a NEW Bosch in the driver's side... I know the 2 brands are ok with our cars, but could using one of each be causing the problem? the headers I have are v6 mustang stock aluminum headers (there are bungs for the O2's in them), into 2 1/2" downtubes to the cats. Before it was 2 1/4. Since the exhaust was changed, I did notice more response/power, but I really don't think this is what is causing the O2 light, but then again I can't be sure of anything at this point...
 
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Yeah check pressure

Check the fuel pressure then go from there.Should be around 39-45 pressure

Just hook a gauge up to the shrader valve on the fuel rail.

Adjustable FPR can be bought at Supercoupeperformance(SCP)

But depending on what you have done to the motor its not really needed.

Tom
 
I checked the fuel pressure at the rails awhile back and it was fine... I guess its not to say while driving things may change. Although the CEL never comes on at WOT - only when I am coasting in gear and slowly let off the gas after driving around 5-15 min... As far as a AFPR I don't know if I need one - my engine is bored .030 over, 10% pulley, I also have a C&L MAF, double IC, BBK TB and a raised top sitting around (not installed yet), and I wanted to get a better fuel pump as well. Would I need an AFPR? Any other ideas on why the drivers side (only) is running lean???
 
Have you already ruled out the possibility of your intake manifold gaskets allowing too much air into the system? Maybe it needs some tightening down or replacement?
 
well the engine was rebuilt less then 5k ago and I used all new gaskets, and had everything tourqued down right - so I dont know how that would even be possible...
 
How many times did you go back and re-torque the intake manifolds to head bolts, and what torque did you use?

Frit
 
to be honest I do not remember anymore - its been over 3-4 years since I put it together, and has pretty much sat around since then till recently. I do remember that I used new head bolts, I vaugley remember tourquing them down at least 2 or 3 times - I remember my grandfather being there, and we were following some direstions :confused::eek: as to the intake manifold - I have no idea... how could that only create a lean code for just the drivers side though?
 
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