dpassino

Hey all, need some input if possible please...

I had a p0171 code according to my reader. I changed the maf as was the general consensus around here for that code. The car would stall like crazy when coming to stops or whenever I got below 1000rpm. After driving around for over 150miles, I gave up and brought it into the dealership who said they would do a diag for 105.00. I was told that not only do I have p0171, their scanner shows..

p0171
&
p0134

1999 Nissan Maxima SE
Cali Spec

They tell me it's an o2 sensor. Bank 1 Sensor 1. The nissan guy told me in the sensor near the fan, that I can reach without jacking up the car. I drove to NAPA and stalled the entire way there at stops. I got the o2 sensor and installed it myself. I drove home and the car ran perfect.. No Stalling. I was like.. PROBLEM SOLVED? NOPE! I get in my drive way and stop and the max stalls. Tried to restart, it would get to 300 rpm and die. I had to hold down the gas when starting to get it back up.

I mechanically inclined friend said if the o2 sensor indeed was bad, that it could possibly be tripping the p0171 code. So I put my old maf back in after a cleaning. I started the car, it stalled once.. I wait a moment, started again and No stall. I let it idle for 5 minutes.. no stall!

So my question is.. CAN bank1 sensor1 actually send over a p0171 code? Could my old Maf be good? And why would a cardone reman maf I got be stalling me out? I'm going to drive alot this weekend and see what happens. I have to do emissions and reregister my car ASAP. I'm already a week late with registration.

dpassino

Looked at a diagram and noticed the nissan guy told me the wrong o2 sensor location. And I can't return a sensor

I'm going to jack up my car and try to just clean the o2 sensor with MAF cleaner spray and see what happens.
I'm angry at the service guy at the dealership.. what a punk telling me the wrong sensor spot.

dpassino

bah, o2 sensor is stuck in position and I can't get a good angle to break it free.. grr.. gonna have to take it into a place with a lift.

nelledge

iTrader: (6)

Try to spray some PB Blaster on it. Let it sit for awhile, then go for a good ride to get the exhaust hot. When you get back, carefully try to take the sensor off while the exhaust is still hot. Side note: I use a Kevlar sleeve when I do mine. It's made more for protecting against sharp objects(metal, sharp plastic, etc) but it works to protect from inadvertantly bumping against hot objects as well. They're fairly cheap and a good investment.

dpassino

Couldn't get it off.. Definitely need a lift for more leverage. When I get the car lifted and clean it, and still if doesn't work, I'll need a new one. I'm having difficulty figuring out which sensor I need... I know it's bank 1 sensor 1, but not sure which sensor I'm looking for through like autozone.com

I'm not sure what connector either... I have 4 connectors by my fan in the front of the car, the left one is in the really short wire and then I have (3) 4 pin connectors. Anyone know which connector or sensor I need to buy for bank 1 sensor 1 at like autozone?

I have cali emissions
99 Maxima SE

I'm confused as to which sensor actually is bank 1 sensor 1. I looked at a diagram, but I have a warpspeed ypipe and the locations are a little different. Is bank one sensor 1 right next to the oil filter or is it the o2 sensor that is on the curved up part of the ypipe right before the flex?

nelledge

iTrader: (6)

It looks like P0134 is the Right Bank in the exhaust manifold. Check out EC-196 here.

Atimaxx

Bank 1 is the one closest to your firewall, ie: the other side of the engine than the the side the dipstick is in. And to answer your question, yes, code: p0171 IS Bank 1, sensor 1 and per the FSM is the specific code pointing to an issue with that O2 sensor or something else. The diagnostic information for this code is from the FSM, page: EC-219. If you dont have this, PM me and I can email you the PDF of the FSM. On this page it says possible causes: intake air leaks, front heated oxygen sensor, injectors, exhaust gas leaks, incorrect fuel pressure, lack of fuel pressure, MAF.

If your car is stalling that is *probably* not a bad 02 sensor. It shouldn't go into a limp mode just because of that, usually it just causes a CEL but should still be able to drive around.

BUT, if your O2 really IS bad and is throwing off the A/F ratio, it could then cause the stalling issues. Sounds more like a dirty MAF or fuel pressure/dirty fuel filter issue. I would try cleaning the MAF like so: http://www.q45.org/maf.html

So, since you already have bought a sensor, you need to replace the correct sensor. Remove your front right passenger wheel, if you look above and to the left of the oil filter, on the header closest to the engine block, NOT the one closer to your muffler (downstream) you should see the front heated O2 sensor with a plug hanging out of it. THAT is Bank 1 O2 sensor. Replace this one with the new one you just bought, clear the codes with a code reader (amazon for under $40 if you dont have one - will pay for itself quickly) or at autozone for free and see how it runs after that. If the O2 was causing the engine to run lean, thus causing stalling, then you fixed the issue, if not, refer back to the list i mentioned about other possible causes.

The FSM is your best friend, I highly suggest getting a digital copy.

dpassino

Thanks Atimaxx, so it's the one next to the oil filter. I'll try to clean or replace that sensor. I can't use the sensor I already bought as it's a totally different connector near the fan in the front of the car.

I did have an issue Long time ago which the code vanished on its own almost 6 months ago.. it was something to do with evap valve stuck open for the fuel I forget the code, but it went away on it's own which makes me think it fixed itself.

I've cleaned the original maf a while ago and still had code after 500 miles, so I bought a new maf from autozone (I live close) which was a cardone brand maf and when I put that one in, the car stalls out like crazy even after 400 miles, so I put the old one back in and no longer stalls, so I am pretty relying that the o2 sensor is failing and tripping MAF code. I don't stall with the old maf, just the new one (which I took out)

I'm looking at a diagram, and b1 s1 is shown to be right next to the flex. (The last o2 sensor in the line) This is what's confusing me.

You say closest to the oil filter... but diagram says closest to flex. I'm using a warpseed ypipe not sure if that makes a difference..

dpassino

is this the right part # from autozone.com ? Part # 13348?

It states....

"With California emission
Front. Downstream sensor (located after catalytic converter)"

Bank 1 Sensor 1 on the diagram above shows "Front" I'm going to assume this is the sensor I need? The cable looks long enough as well.

If I'm totally wrong, please help me find the right part from autozone (direct fit) I don't want universal.
1999 Nissan Maxima SE, CALI spec.
I'm getting so burnt out over this.. emissions way late, registration expired.. I don't have much longer till I'm out of my registration grace period

dpassino

ok folks, sorry, but upon looking into this further, I notice that there is a o2 sensor connector right under my front strut sway bar in my engine bay, with a flash light I see the cable is under 2 feet with an oval grey connector which I have an extra one here at the house. I will have to lift the car with some jack stands, but is that B1 S1? I think I found it, please tell me I'm right! LOL

dpassino

Well my Code went away after replacing Bank 1 Sensor 1 in the correct position. PHEW..

Drawback... another code that I had last year is back... p0440 and p1448 (vent control valve stuck open)

When I tried to clean it per a writeup I found, the valve wouldn't budge. after about 10 minutes with a qtip, lubricating spray and a long nail, it seems to move back and forth freely at the moment. I'm hoping that is all I need to do. Was easy.. I'm not used to easy problems...hehe I cleared the code.. If the light comes back on with same codes, should I just replace the piece?

Crusher103

iTrader: (10)

if u dont live in Cali or NY, convert ur car to a 95 fed spec. Easiest way to solve the problem.

dpassino

Phew! Emissions Passed! Thank God! hehe