Code P1171

[snowtrooper1966]

Wierd...
I cleared the codes and then got some MAF cleaner. The check engine light usually comes back on in a few miles. It stayed off all day yesterday. I did not get a chance to clean the MAF yet. I will do it today and keep you all posted.
Best,

[crager34]

Cleaning the MAF is super easy and won't cost you much time at all, AND it's worth it simply for preventative maintenance.

[Vendetta]

Forgive my waking this tired 'ol thread, but I'm having the EXACT same codes thrown at the moment.

P1171 - Fuel System Lean During Acceleration
P0157 - O2 Circuit Low Voltage (Bank 2 Sensor 2)
P0137 - O2 Circuit Low Voltage (Bank 1 Sensor 2)

My wrench swears up and down that he already replaced all the O2 sensors with brand new ones. He's at a loss. Therefore I am at a loss.

Snowtrooper, can you put please a ribbon on this one and tell us if and how you solved this set of codes?

Thanks,
-V

[Ldub]

Forgive my waking this tired 'ol thread, but I'm having the EXACT same codes thrown at the moment.

P1171 - Fuel System Lean During Acceleration
P0157 - O2 Circuit Low Voltage (Bank 2 Sensor 2)
P0137 - O2 Circuit Low Voltage (Bank 1 Sensor 2)

My wrench swears up and down that he already replaced all the O2 sensors with brand new ones. He's at a loss. Therefore I am at a loss.

Snowtrooper, can you put please a ribbon on this one and tell us if and how you solved this set of codes?

Thanks,
-V

I'm fairly certain that those codes are indicative of unmetered air getting into the intake system, somewhere downstream of the MAF sensor.
Could be vacuum leak (hose or otherwise)
OR, vacuum leak (intake manifold gaskets)

Look HERE

[Vendetta]

Thing is, my wrench cleared the codes this morning prior to my 100-mile trek to the yard and back, and they haven't come back on.

Granted, I was driving on eggshells going for maximum MPG, but still... I would think they'd come on if it were something like a gasket leak. I don't know, so here I am.

-V

[Ldub]

Thing is, my wrench cleared the codes this morning prior to my 100-mile trek to the yard and back, and they haven't come back on.

Granted, I was driving on eggshells going for maximum MPG, but still... I would think they'd come on if it were something like a gasket leak. I don't know, so here I am.

-V

Yep...

Same experience, as long as I'm a "good boy" with regard to the skinny pedal...nothing.

But when I drive "normally", I would get the same codes. Start with a good maf cleaning...

[Cobrajet]

Thing is, my wrench cleared the codes this morning prior to my 100-mile trek to the yard and back, and they haven't come back on.

Granted, I was driving on eggshells going for maximum MPG, but still... I would think they'd come on if it were something like a gasket leak. I don't know, so here I am.

-V

Yep...

Same experience, as long as I'm a "good boy" with regard to the skinny pedal...nothing.

But when I drive "normally", I would get the same codes. Start with a good maf cleaning...

I had that P1171 code years ago, and it would go away for days, only to return when I took one particular uphill stretch from a right turn. Because it was a 50 mph zone following a blind curve I always had the pedal to the metal. I had the dealership clean the MAF on my next service call, and I replace the K&N filter with a stock one, and have not had another code since.

[Child's Play]

Forgive my waking this tired 'ol thread, but I'm having the EXACT same codes thrown at the moment.

P1171 - Fuel System Lean During Acceleration
P0157 - O2 Circuit Low Voltage (Bank 2 Sensor 2)
P0137 - O2 Circuit Low Voltage (Bank 1 Sensor 2)

My wrench swears up and down that he already replaced all the O2 sensors with brand new ones. He's at a loss. Therefore I am at a loss.

Snowtrooper, can you put please a ribbon on this one and tell us if and how you solved this set of codes?

Thanks,
-V

V,
Just got the same code today as well.... Must be the nice weather. Anyway, on my last VX I had this code as well and it was the intake gaskets (very common). I'm gonna take mine in shortly to have it diagnosed, but I'm pretty positive this is what it is as I hear a slight vacuum sound coming from the engine bay.

What is the mileage on your VX? Mines @ 72K

CP

[Vendetta]

Hey CP,

I'm at 90K now. And the CEL is doin' its thing. I've cleared it a few times, but like Dub says, when I get on it a bit, the light comes right back on and stays on 'til it's cleared.

I'll have my guy look at the gasket leaks - eventually.
-V

[89Vette]

Hey CP,

I'm at 90K now. And the CEL is doin' its thing. I've cleared it a few times, but like Dub says, when I get on it a bit, the light comes right back on and stays on 'til it's cleared.

I'll have my guy look at the gasket leaks - eventually.
-V

If you've got a propane torch, just turn it on and run it around the perimeter of your intake. If the engine speeds up, you've got a leak. Some people use starter fluid, but it can be a fire hazard if you've got spark exposure.

[Vendetta]

Good tip. Sounds like an even better option than spraying cleaner around it. I'd hate to make a clean spot!

I'm putting on a supercharger in the coming weeks (months?) so this might be a moot point, but I'll probably still try it.

-V

[Ldub]

Good tip. Sounds like an even better option than spraying cleaner around it. I'd hate to make a clean spot!

I'm putting on a supercharger in the coming weeks (months?) so this might be a moot point, but I'll probably still try it.

-V

DOOD...

You just jarred some cobwebs off the noggin...

I just found my Alpine S/C install material in the garage this weekend.

Scanned & converted to pdf, & shipped it off to the Boss for the DL section.

I know how busy he is, especially right before Moab, so if you want me to email you the files, lemme know....