Heyaaaa! Yea It's me.

Yep, I got those 2 codes.

So ... system running lean.

As far as I remember there were no Vacuum leaks on the car ... drives fine and stuff ... idles perfect.

if I erase the code with my handheld reader, it comes back on the 2nd drive cycle. always. so I assume I have a leak somewhere ... ? and system must be running really lean cuz I don't even rev it high and I still get the code.

I tried to search (OH BELIEVE ME I DID) and there were so many answers to this.

- fixed with a new exhaust gasket between manifold and cat
- New Oxygen Sensor, Front and/or Rear
- some fixed it with a new gas cap (yeah, wtf?)
- Weak Ignition (see below)
- Fuel System issues (see below)
- Engine is fucked up. (I wouldn't be surprise cuz this is a Mazda Reman)

hmm ... at first I thought I had a vacuum leak but I looked thru everything I can't find anywhere ... I changed the airbox assembly cuz the threads on the MAF are messed up. changed it with new filter. still came back on 2nd drive cycle

Next thing on the list will be oxygen sensor. I wonder how often do they malfunction, I believe I changed my front O2 sensor maybe 30K miles ago. Never touched the rear tho.

I have RB flash btw, but never had any problems with it till now, like I said before I don't even rev it high and I still get the code. RB flash does not modify anything below 4K rpm.

coils are new have couple K on it (I rare drives the car these days), same thing for plugs and wires.

I used to be able to read the STFT and LTFT with sCANlyser, but as EVERYBODY know the support on that "thing" is almost non-existing, and it was the old version with serial port, it does not work with USB to Serial Adapter (the program always f-king crashes). Does anybody know what other options do I have?

I don't think it's the O2 sensor but is it possible that it could be "on it's way to O2 sensor heaven" and giving the PCM all kinds of wrong info ? Just in case it's the O2 sensor I always ordered 2 new ones(front and rear) and it should be here today. I won't change it yet. Just in case.

Hmm oh yes Fuel System, I used to get lean code when my Fuel level gets low + do some high rpm revving. Stupid fuel pump, could it be the pump dying AGAIN??? **** really I just changed it like maybe 20K ago.

Ideas ! I need Ideas !

 

Have you cleaned the MAF yet?
That's typically step 1 after making sure there aren't any intake leaks.

What was the last thing you worked on on your car?
Maybe go back and double check that a hose didn't slip off, or something.

BC.

 

Does sound like an intake leak - just to make sure, spray the whole area with brake solvent, one hose at a time, you might find a crack......

There is always the dirty pump suction sock, but I always say that.

 

Last thing i did? Replaced a starter. But i had that cel before i replace the starter, i first thought it was the netural switch cel cuz i always get that every winter.

Maf? Hmmmmmm, i changed my maf couple months ago with a brand new unit. Not that the old one gave me any cel but i was like maf just like any other sensors, might wear out and give me wrong readings.

But isnt a system run lean code cause by o2 sensor closed loop readings and not maf open loop readigs?

I will try to swap the maf back to the old one tomorrow, delete the cel and see what happens.

Thiught about the socks too, but if i have to take it out and clean it, might as well replace the garbage pump with a walbro unit then burn shut the valve?

 

I had the same codes on Hoss-05's car and it was because one of the caps on the service nipples on the lower intake manifold was missing. 2 second fix.

Do you have a hand held propane torch?

 

who is this nycgps noob ?

 

I checked, no nipples missing >_<

for ?

Yeah, I was wondering the same thing

 

I swap the maf back to the old one, reconnect battery, idle does not jump as crazy as the new maf.

Gonna drive it for a few days see what happens.

Oh also, where does this bracket connected to, it has been hanging like this for a while, i think wayne mazda forgot to reinstall this back when they did my engine 2 yrs ago.

 

oh ****, I think it could be the MAF.

so far 2 drive cycle, no CEL, no stored code. mmmmmmmmmmmmmmmmmmmmmm

lemme drive it for a few more times see what happens. Ahhh ****. RMA time ?

 

Follow up? WHY DONT YOU FOLLOW UP?!

 

I believe it's the "new" MAF hate me or some **** and gave the ECU weird readings.

Old MAF back, no store code, no CEL, nothing. car is running happy

Note to self --- Buy lifetime warranty stuff next time. Lucky this MAF is not that expensive.

 

I am experiencing the same exact thing. No apparent vacuum leaks. Car idles very well for the mileage on the plugs. New BHR coils, no exhaust leaks, cleaned the fuel filter, not dirty. No loss of power, reaches redline fine and dandy.

Original MAF for me, cleaned it multiple times. CEL comes on every, or every other drive cycle, no set pattern, just out of the blue. 55k miles.

 

My CEL came on while coming to work. Idled fine at a few stopping points. Once I got into the parking lot at work, the car shut off. Now when I did tried to restart the car, i had to hit the gas pedal alittle to keep it idling so it won't shut right back off. Luckliy, a guy at work carried an OBDII reader in his car.

Used it and got this code: "P2096 - Catalyst Fuel Trim Bank 1...Too Lean."

During lunch break, I'm going to check for any loose hoses and recheck to see if I have a vaccum nipple missing. And this happens after I have gotten gas from 7 Eleven almost running empty in the tank. Around my way, it was the only place opened late in the night. And fro the store I hit a damn dog... Not bad damn. Thinking maybe from the hit, a hose might have losen, but the impact wasn't that hard. I'm think the bad case of horrible gas from 7 Eleven.

Do any of y'all suspect it's more towards having bad gas as well as I do? Think any kind of trreatment would help?

 

Damn, I made a run during lunch to AutoZone for to get some gas treatment to try. As I leave to head back to work, I get to a stoplight and after 3 seconds the car idles low and shuts off... SMH... Took a minute for me to get it back started. I was trying to be care on not pumping too much on the gas pedal.

 

Ok guys I delt with a lean code for 7 months. I had maf, both o2 sensors, coils, fuel injector cleaner two or three times, fuel pump, oh and engine all replaced. Each time it went away for a few weeks. Then the last time mazda had my car for 5 weeks and found my fuel injector gaskets were leaking air. Got the gaskets changed and new injectors and I've been good for a few months now. Just giving you my experience with p0171 of death.

 

Most likely your Catalytic is done, or the Rear O2 sensor.

Check your cat first.

 

Thanks for the info!

I've heard of this before.
It knaws at me in the back of my head when I change my injectors.
It's a bit of trick to get those things to seat correctly.

 

unmetered air will always cause this CEL

not to mention all other electrical issues that can trigger this "event"

and it's a PITA to locate it ...

as our 8 aged, I think more and more of these "weird" p0171 will come ...

 

Thanks. I will check that out too. So far I had cleaned the MAF sensor and changed the air filter. The engine light is off and car idling fine. But I will check the cat. anyway probably tomorrow morning.

 

That's typically step 1 after making sure there aren't any intake leaks.

 

Just got mine today, new plugs, mazport ignition, clean MAF etc. tons of rattling from my RP super cat, I think the cat may be the problem.

 

I had the P0171 code throw up after I went to the exhaust shop to take care of two exhaust leaks. We found that two gaskets had blown out causing a leak post sensors.

To work on the car he sprayed water onto the exhaust very close to the rear o2 sensor.

After we started the car the engine light came on right away. We cleared the code and did not reappear on the drive home. I will monitor this and hopefully if should be ok.

The car was tuned with the exhaust leaks in place will fixing the leak cause a lean condition?

 

Shouldn't cause any CEL.

 

Ive always wondered about this. I dont have nipple caps on mine, I have a bigger hose going from the top of the oil filler cap down to the lower intake and splitting off into 2 smaller hoses and going into the intake. Is my car a special one or something?

 

your car has the SSV update installed, which is normal.