please help : problrm in legacy 2010

[kalabala2005]

i have problem that my car smoke black

and when i check spark plugs it was so black as below photo and car was run so weak .. what should i check and what is the reason for this ?

 

http://prntscr.com/has0te:spin::spin:

 

1- how to check if maf sensor is damaged

2- i change spark plug and car run OK now but i think after 2 days it will back again .

3- what should i check to know why my spark plug get black

4- the oil is ok and no any lack on it ( i mean no decreasing in motor oil )

[BarManBean]

What plugs are you running?

 

Carbon-covered plugs like that along with black smoke would both point to the car running really rich (too much fuel). You could have a pretty bad boost leak. Damaged MAF might also be an issue.

[A_A_ron]

I don't want to sound insulting but the black smoke and incomplete combustion sound like you might have gotten some diesel fuel mixed in with your gas. If you have any question on the contents of your gas tank I would drain it completely (please dispose of bad gas in a proper manner) and then fill it up with 91 octane no ethanol gasoline to be sure you have good gas.

[A_A_ron]

Paging Zee199969 to weigh in on this issue. We've lost a lot of Legacy in the last two weeks, hoping we can save this one.

[Zee199969]

Paging GTEASER/islandborn/s2baru on this since this is beyond my knowledge

[Zee199969]

but first off kalabala2005, what's the model and year of your legacy?

[cww516]

Do all 4 plugs look like that, or just the one? If it's just that single plug, there's a chance that injector is stuck open.

[A_A_ron]

good point cww, btw kalabala2005 is this a turbo model? NA 2.5i? or a 3.6R? Is this JDM USDM or some other country model Legacy?

[kalabala2005]

Its legacy 2010 fifth generation n/a ej 2.0 im from egypt

 

I change spark plug and change maf sensor and car run good now but im afraid that car will do same thing again ?? But how i see if my car run too rich or no ..??

[kalabala2005]

Yes all 4 spark plug are black ..

[Zee199969]

but im afraid that car will do same thing again ?? But how i see if my car run too rich or no ..??

 

You'd need an ECU reader, but I am unsure what is compatible with your car

[cww516]

Since all 4 are black, I wouldn't rule out the front O2 sensor, either. If that's in rough shape, it could be reading a much leaner air/fuel ratio than what a healthy sensor would read. Those are expensive enough (and enough of a headache to change) that I'd test it to see if it's bad before just throwing parts at the problem. An exhaust leak near (or even just upstream) of the front O2 sensor could potentially do the same thing, since you'd be mixing in clean air and making the sensor read lean.

[FLlegacy]

Is this a direct injection engine? Hard to imagine the ecm was happy with all that unburned fuel. Definitely need to put a scanner on it.

 

Sent from my SAMSUNG-SM-G920A using Tapatalk

[kalabala2005]

I have ecu reader ... what parameter should i see on it to see what is the error ..

I have obd2 tool and have vag cable and sst program and its read my ecu ... but can u advice me what value should i trace it please ??

[A_A_ron]

Can you make data logs or have your ODB2 tool display data in any way?

First see if your ECU reader shows any error codes if so post them all here with as much information as you can.

Second see if you can data log or have the ECU reader show data. Things that might help determine the issue include.

-Knock

-AFR

-Fuel Pressure

-Throttle Position

-DAM

-MAF

-AF correction

-AF learning

Not all of these may be available but gather as much as you can.

[cww516]

This may be where I tag out. I'd say look for parameters relating to the front O2 sensor, may be called either an oxygen sensor or A/F sensor, and maybe see if there's a way to get a raw readout (resistance or voltage) as well. You should see changes in that value when you go from coasting in gear to pushing on the gas pedal- if it gives you air/fuel ratio, it should say something near 14.7:1 when you're cruising at constant speed (or idling after it's warmed up), and probably something closer to 20:1 if you take your foot off the gas. If it reads anything much leaner than this (meaning the first number is bigger, so 16:1 or 17:1), I'd look at the O2 sensor as the culprit. If it reads richer (first number is smaller, and if you're blowing black smoke, it'd be closer to 10:1), I'd look at something upstream like the MAF sensor. Since you said you already replaced that, if the problem doesn't come back, it's entirely possible that it could have been the MAF sensor.

[Perscitus]

If its a generic OBD2 reader/app that kalabala2005 has access to, then he's likely only got access to very basic OBD params such as:

 

Long-term fuel trim

Short-term fuel trim

AFR

AFR or Lambda target

MAF (likely just g/sec or voltage, not both)

Throttle % (no plate or pedal position)

maybe Boost (as a Vacuum gauge)

No DAM/IAM, FKC, FLKC, Fuel Pressure, Engine Oil Temp, Intake Manifold Temp

 

And yes, even Long-term and short-term fuel trims for Bank #1 will be a bit telling.

[GTEASER]

I'm here to help but it seems like most of you have it covered. I can't think of anything else it might be other than things already stated.

[aperson]

Did you check the plug gap on the old plugs when you replaced them?

If the gap was too wide I could see it not fully igniting the air/fuel mixture which could lead to this but if that's within spec I'd say there's a dirty/dying sensor somewhere which is telling the ECU to dump fuel (see Persiticus' posts for info on that)

[FLlegacy]

My global scanner doesn't give me too many of the same things the AP does, it gives O2 sensor voltages not AFR readings. It is very raw data.

[cww516]

A voltage readout from the O2 sensor is good, too- if it sits constant at one value (whether that's 0V, 5V, or 12V), that's bad. I'm not sure which end is rich and which is lean, but there's a fair chance that the actual "normal" range is something like 0.5-4.5V, so that anything outside those ranges is flagged as an error. Hopefully someone who actually knows what they're talking about can chime in and clarify that, though.

[kalabala2005]

i log the car today and here in attached all what i get ; can anyone help me what should i concentrate or what is the wrong ??

 

http://prntscr.com/hb46x2

http://prntscr.com/hb471c

http://prntscr.com/hb474s

http://prntscr.com/hb477y

http://prntscr.com/hb47c6

[A_A_ron]

Okay so it looks like you grabbed all the data for 660 rpms and it also shows min max. If possible try to get data for 2k rpms and maybe another sample say 4k rpms. This will let us compare the values across various engine speeds. Also try to run the car a little a possible, even only just for the test. Don't want to cause more damage if it is.

[Perscitus]

FreeSSM is certainly better than a generic OBDII app such as Torque.

Although its still ancient tech by now, but for this I guess it will do.

 

Scale back the fields you're looking it to what others have recommended and save a idle log (~5 minutes at operating temp), cruise log (~2-5 minutes, stable throttle, say 4th or 5th gear, no gear changes, no throttle blips), gentle acceleration log or hill-climb in a higher gear (say 3rd).

[kalabala2005]

The car is stuck on 2k and no response car is stuck i mean so heavy on 2k then i must push gas to 2.5 or 3k and car run so good above 2.5k till 6k wery good ...car is run so bad on 2k stuck in 2k ..i hope i can explain my issue