Help! From check engine light to fouled plugs back to check engine + plugs refouling
 

Hi all,


Ill start with its a 2013 BRZ ive owned the whole way, 45k on it. Driving back from hockey one night the check engine light came on. Dutifully I went to the dealership the next day, they said something about an issue with engine imbalance and they would need it for a full day and I could drive it the few days in between. They have now had it for 1.5 days and called me to say its running "better" that the spark plugs were fouled and then questioned if I had been putting premium in. I have only EVER filled up with Shell V-power, which is 91. They are going to keep looking at it.
I'm not exactly a gear head, so any help understanding what is going on would be much appreciated. I am worried in general about wtf is going on, again since I have only EVER put 91 into it. Should I be concerned about other possible related issue, now and down the road, and is there anyway to gather evidence from the car that I can go after the dealership for faults or even Shell for faults.
I have occasionally switched between sport modes, and its an automatic fyi.
Thank you in advance.

:popcorn:

Your car will be fine. You are overthinking it. The dealership will take care of it and fix the issue.

Shell V-Power is 93, if I am not mistaken.


Either way, I am sure your car will be fine. Pay attention to it when you get it back - just do not let that morph into paranoia.

It's 91 in these parts ........ ;)


humfrz

+1 91 here. I used to run it until I went full retard and use 94 now

Petro Can Petro Can you're the only one with 94 octane (spiderman theme)...around here anyways!


Why wouldn't you use 94 octane if it's avl, the diff in price is negligeable and there aren't any downsides :)

I only use 94 and the way my car is tuned I cant run 91 or it pulls timing and I cant go down to sea level anymore either lamo (hence the full retard part)

WTF you can't go at sea level??(I'm puzzled by that statement). I'm also tuned for 94, although I do have a 91 tune somewhere in the ecutek shit in case I'm in no 94 land. Summer is around the corner :) time to start shopping gauges and log some runs to get a revision done on my 94 tune :)

Nice to think positive but you can not count on that! Just the fact that they tried to already blame him by questioning the octane of the gas he uses tells me they are already hunting for an excuse not to cover the work.

If the dealer ever says something about blaming you, tell them to piss off and look for another dealer.

Your under maintance and the only thing you done is fill up the gas and oil, you have no fault. Sounds to me like the dealer is trying to pull a fast one on you.

There has been a few owners that reported defected ignition problems. With cars under 2k miles.

And FYI here in California our top octane is 91.

They are just asking questions doing their job making sure the issue isnt caused by something silly like that before they dig deeper into the issue. I am sure he will be fine

It'll be fine, relax bro

Technically the car can still run on 87, but you just won't get the same power. The car isn't going to explode with 87. The car has knock sensors and if it detects knock, it will retard the timing.

If they say it's the gas and you didn't use 91 and caused the car to blow up, we'll that means the car has a problem and won't detect engine knock so it's they need to fix the car.

Smells cattle excrement they feed to their average customer so they can charge what they want. Fouled spark plugs stopped being common 5 years before I was born. Ask for the code that was stored on the ECU that caused the check engine light. There is zero reason why they should deny giving you that number. If they don't have it then they can't fix a problem they aren't aware of and are, again, bullshitting you by keeping your car if they aren't doing anything about it.

For background fouled spark plugs mean that the air fuel ratio is incorrect, this is tightly controlled by your ECU, O2 sensors, timing and fuel injection systems. If your spark plugs are fouled and they aren't replacing or changing one of those things they're either feeding you bullshit or being lazy about fixing it. For any one of those things to go bad before 150k miles on a modern car at the earliest is nearly unheard of.

Throttle body and injector cleaning are snake oil.

.........and .......if they ask you if you have been filing down the ignition points with your mothers cardboard finger nail file or you have been fiddling with the carburetor's idle screws .......... take it to a different dealer ......:eyebulge:


humfrz

Yup, I'm pretty sure "GTA" is in California, and they only have 91 or lower....

GTA=Greater Toronto Area in Ontario, Canada. Common mistake. I'm a courier, and Ontario CA could mean either the city in CAlifornia or the province in CAnada.

The fact that is profile says he has a BRZ Sport Tech is telling in it's self. Anybody in Cali have a Sport Tech?

I was hoping somebody would mention this (I should have know who would). I haven't seen a fouled plug in 20 years. Sure it used to be an issue but more with carbureted engines and pretty much went away with injection. If plugs are actually fouling there is something very odd going on. Sounds like a feeble excuse on the tech's part. Besides how old was that tech?


http://farm6.static.flickr.com/5051/...c8ed7c625f.jpg

My bad, when I think GTA I think California, I'm from the USA :lol:

Born and raised Californian, only relevant acronym I could think of is Grand Theft Auto and the only way that's relevant is the video game.

I didn't know GTA was Toronto until this forum either.

Update:


Got the car back same day as original post. They said with the new spark plugs, and vigorous testing, that the car appears to be running as it should be. I didn't ask for the code that triggered the engine light, but I will next time I get it serviced.
Car appears to actually be running a little better than when I took it in, based on when my RPM is hovering at certain speeds (no actual idea if this is a good gauge for that lol). I appreciate all the feedback, and will be keeping a close eye on things. May consider switching to petro if I hear anything fishy going at on at shell, but I would miss my airmiles :/
Only other thing is the steering feels a bit stiffer than I remember, but maybe just adjusting back from the use of my mom's civic.
Anyway, thanks again all - and I will remember to investigate the code.

Update:


Check engine light came on AGAIN. Steering feels a little more forced that it used to, I think. Will see what happens when I deal with the Mississauga dealership again tomorrow.
Any advice is appreciated, thanks.

Before you go in, go to an Autozone or Canadian equivalent and borrow an OBDII scanner to check the code. The early cars had some issue with cam angle sensors I believe so I wouldn't be surprised if that is the sort of issue you are running into. That issue is detailed below.

http://www.ft86club.com/forums/showthread.php?t=45844

Got the code, will update with it later (wrote it down, but no access to it atm).


Definitely some power drain, mileage is dieing, and jerking when down shifting - some very noticeable drags (between gears?) when decelerating - most noticeable from 25km/h to 15km/h. Its automatic btw.


I reset my avg fuel consumption when I got the car back, was at 7.5k/100l thru the winter, and with summers on now I'm at 7.9...so something is definitely going on. Not happy right now, worried I'm gonna end up paying for this more down the road.

Sounds like an issue with the electronics: bad sensor or something and the ecu doesn't know what to do with it. My .02$

I don't think anybody ever responded to this. Altitude has an effect on the octane required. Because the air is less dense at higher altitude, the engine is less susceptible to knock. As a result, you can use a lower octane gasoline at high altitudes with any detrimental effect on your engine. If you ever go up to Taos, Santa Fe or Los Alamos (around 7000' elevation), "regular" gas is 85 or 86 octane, and at some stations the highest you can get is 89.

The opposite is true going down to sea level, where you'd need a higher octane for the denser air. If go_a_way1's location is correct, he lives at an elevation of about 3400'. If he's tuned for 94 and it's as limited as he says, he might need 96 or 97 octane at sea level to avoid knock. Since you can't buy that at the local corner station, he might have some problems.

Original code was P219A
They also threw GHQ42 at me, not sure whether its related.
Will find out more on Tuesday!

So the new plugs they put in are fouling again. They are going to replace the ignition coil. Beyond this and original code I don't have much idea whats going on.


Any questions I should ask?

P219A is air-fuel ratio imbalance. I am now thinking much less that the dealer is full of sh*t, and more that they may be on to the problem. GHQ-anything is the wrong format for an OBDII code, so I'm going to assume that's a mis-transcription and ignore it.

In your OP you told us the dealer said "something about an engine imbalance." I was initially skeptical, but seeing the code, I now see that it was a legitimate attempt to relay information, buried in a mis-transcription. However, given the nature of your post, I take it you are not well-informed. Let me fix that.

If the car is running very rich, it will do the following:
-throw that code,* and
-foul the plugs.

* In order for the code to trigger, and the plugs to foul, the engine must be running richer than commanded. (as opposed to leaner than commanded, which would have made different, albeit more exciting, issues for you)

The ECU commands a given air-fuel ratio at a given RPM and engine load; Load, defined as the mass of air entering the engine per rev. The ECU uses sensors to calculate the load, (one sensor for engine speed and a number of sensors to approximate airflow), and opens the fuel injectors by applying power to them for a calibrated amount of time (called the injector pulsewidth) to deliver a calibrated amount of fuel.

The ECU monitors how well it's doing it's job via an oxygen sensor in the exhaust, the readings from which can be used to calculate the air-fuel ratio of the burned gases coming out of the engine.

In fact, under stable conditions, your ECU uses the information from the O2 sensor to correct its fuel delivery schedule, and get closer to the target air-fuel ratio. This is called closed-loop correction.

Following me? good.

In order to throw the code, the input from the O2 sensor must be out of the acceptable range - either rich or lean. If the sensor is bad, it could throw the code when everything is otherwise just fine. BUT your plugs are fouled. That tells us three things.

1 - The engine is, in fact, running outside of the acceptable air-fuel ratio range.
2 - It is running unacceptably rich, not lean. Ergo, your plugs are fouled.
3 - The oxygen sensor is working correctly. This is im-por-tant because a faulty O2 sensor can cause a rich/lean problem by itself... But that's a closed-loop discussion for another time.

From the information I've already given you, there are 2 possible answers:

1 - Injector or other fuel delivery problem (You have 8 of them, 4 port, 4 direct, and 2 pumps. Each is what engineers like to call a single-point-of-failure for the entire system.)
2 - Air sensor problem (likely the Mass Air Flow sensor, [MAF] as that is the primary input to the ECU for air flow)

There are many ways to narrow down the problem from there. For example, your dealer said plugS were fouled... I'm assuming that means all of them. That fairly well rules out a single injector. P219A means imbalance in bank 1, but that's funny because despite having 2 banks of cylinders, this engine has only 1 oxygen sensor, and therefore, not "bank 2" code at all.. Yep, no P219B for you.

This points to a problem in all the cylinders, which points to an air metering problem.

This engine uses a hot-wire MAF, the operating concept of which I will not take the time to explain. Suffice it to say, any increase in electrical resistance in the MAF circuit (loose wire, fouled contact, chafing, damaged or broken housing, or just poor quality control) will cause the engine to think there's a whole bunch of extra air coming in.

Just theories... All of it.

Read my previous post first....

NO NO NO NO NO NO NO NO NO. F*cking mechanics.

REPLACE THE COIL? Singular? There's 4 of them. 1 for each cylinder. Sounds like some missing information here. Also to answer your question YES. I would like to know which plugs are fouling. All of them or just 1? From your vague description, it's now hard to tell. And from reading my last post you should be able to tell the answer is important.

Replacing fouled plugs and coils and hoping the problem will go away is a bullshit band-aid fix that won't work for long, if it even works at all. That's just mechanics being lazy and not wanting to put in the work to diagnose the actual problem.

It's like putting a towel over a compound fracture and hoping it will go away if you don't look at it. The mechanics know that too, they're just being lazy... I know because I know many mechanics, and often have to beat them into getting off of their lazy asses and doing some real diagnosis.

If the coils were bad, the engine would throw a code to indicate the coils are bad.


The fact is, like many other people have already said, modern EFI engines DON'T FOUL PLUGS. If it's fouling plugs, there's a problem that needs to be fixed, not just replace the f*ckers and hope they don't foul again.

Thanks for the info spartarus
I will be finding out more tomorrow and will ask for codes and which plugs are fouling etc.

DANG, larchamb ....... either those folks you are taking your car to, don't know what they are talking about/doing or you are interpreting/relating what they say, mostly wrong.

I sure hope your car gets righted.

humfrz

Here in PA and NC are all the other US states it mostly is except in cali, in that area of canada it isn't.

Agree with what @Spartarus says.

another cause could be leaking,cracked header or leak near primary 02 sensor. The 02 sensor then sees fresh air, ie detects lean condition especially at lower rpm, the ecu then compensated by adding sh1t tones of fuel using the fuel trims and you end up actually running rearly rich (usually indicated by high positive long term fuel trims like 20% plus), but the 02 sensor still gets bursts of fresh air so ecu keeps adding fuel.

As we only have one 02 sensor for fueling all four cylinders will run rich.

seen this happen a lot with guys changing to aftermarket header but could still happen with stock header if crack leak developes and some 02 sensors have been cross threaded from factory

Update:
Same code had popped: P219A
They replaced the #4 Ignition Coil and that spark plug.
Originally they replaced all 4 spark plugs.
It is an open case still, they didn't want to rack up km's testing it, so let me have it back and I will obviously take it back in if something else shows.


They updated ECM, said that downshifting kick should be solved with that.


All in all the car is running as I think it should be, much more fluid in speeds and no more drag.


If light comes on again, ill have them read this thread lol

Glad your car is running better .......:thumbsup:


humfrz

check engine light back, and kick on deceleration at approx. 18 km/h
lol.....sigh

I think I might start looking into the operation of your local lemon law.

get the dealer to log the long term fuel trims LTFT if they are over 10% or so then something is wrong with the fueling likely stuffed or dirty sensors ( 02 or maf) or injectors or intake exhaust leaks.