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Smoke from exhaust

11574 Views 55 Replies 14 Participants Last post by  thecomputerguy
As of yesterday I put on 250 easy miles and throughout the day my cousin behind me said when I get on the throttle it blows smoke from the exhaust pipe. Smells like un burnt fuel so I'm guessing I'm running rich but why all of a sudden now? 2400miles on the bike. I also noticed its been back firing more and more. I have a cobra slip on exhaust but have had that on since new. Any ideas anyone???
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Might be time for a diognostic test. Possibly a censor in the closed lope system has gone bad causing it to bur rich. 02 censor is one. If you unplug that one and there is no change that may be it.
Maybe you might be the first to see if you can access the diognostic mode via the digital display to get the error codes.
Here is how you access it. Have not tried this so proceed at your own risk.:wink:

1. Press and hold the Reset button
2. Turn ignition to ON and keep holding the Reset until "diag" appears on the LCD (about 5 seconds).
3. Now press and hold Reset and Select buttons at the same time and hold for about 5 seconds until you enter the diagnostics list.
4. Now you can press Select to move up, or Reset to move back through all available code. Among them are throttle position sensor, temperature etc.

01 : Throttle position - must be from 15-17 (closed) to 97-100 (opened)
02 : Atmospheric pressure given in mmHg (normal is 760 - average weather)
03 : Differential pressure between air and intake pipe
05 : Air intake temperature (in Celcius)
06 : Cooling liquid temperature (in Celcius)
07 : Absolute speed (must be 000 in garage). Check with rear weel.
08 : Lean angle safety switch control - must be from 0.4-1.4 (upright) to 3.8-4.2 (horizontal). DISMOUT THE SWITCH FOR CHECKING !!!
09 : Battery voltage - must be above 12.0
20 : Side stand switch - displays ON or OFF
21 : Neutral gear switch - displays ON or OFF

Part II : ECU memory check.

60 : EEPROM error code presence - 00 means no default, 01 or 02 means default on corresponding cylinder (blinks if both cylinders).
61 : Error Code memory log - Displays 00 if no error code in memory, displays the Error Code if any (11 to 50). Display changes every two seconds if more than one Error Code in memory, then start again from first.
62 : Displays the number of Error Code in memory. To clear the memory, switch the Engine Run Switch to ON position (no backup).
70 : Check Code number, display from 0 to 255

Part III : Activators - To activate, turn Engine Run switch from OFF to ON - Engine check light is activated too.
30 : Coil 1 is activated 5 times per second.
31 : Coil 2 is activated 5 times per second.
36 : Injector 1 solenoid is activated 5 times per second.
37 : Injector 2 solenoid is activated 5 times per second.
48 : Air duct solenoid is activated 5 times per second.
49 : Air intake solenoid is activated 5 times per second.
50 : Fuel injection relay is activated 5 times per second.
51 : Cooler fan is activated every 5 seconds.
52 : Headlight relay is activated every 5 seconds (2 seconds ON, 3 seconds OFF) - 2003+ model only.

Error Codes
Error Number 11 : Cylinder identification sensor error - DIAG mode (none)
Error Number 12 : Crankshaft posiiton sensor error - DIAG mode (none)
Error Number 13 : Air intake pressure sensor error - DIAG mode 03
Error Number 14 : Air intake duct error - DIAG mode 03
Error Number 15 : Throttle position sensor error - DIAG mode 01
Error Number 19 : Sidestand sensor error - DIAG mode 20
Error Number 20 : Air pressure sensors error - DIAG mode (none)
Error Number 21 : Coolant temperature sensor error - DIAG mode 06
Error Number 22 : Air intake temperature sensor error - DIAG mode 05
Error Number 23 : Ambient air pressure sensor error - DIAG mode 02
Error Number 24 : O2 (lambda) sensor error - DIAG mode (none)
Error Number 30 : The bike went down - DIAG mode 08
Error Number 33 : Coil 1 open circuit - DIAG mode 30
Error Number 34 : Coil 2 open circuit - DIAG mode 31
Error Number 41 : Tilt sensor error - DIAG mode 08
Error Number 42 : Speed sensor error / Neutral sensor in short-circuit - DIAG mode 07-21
Error Number 43 : Battery voltage control error - DIAG mode (none)
Error Number 44 : EEPROM read/write error - DIAG mode 60
Error Number 50 : ECU memory error - DIAG mode (none)
Error Er-1 : ECU link error
Error Er-2 : ECU link error
Error Er-3 : ECU link error
Error Er-4 : ECU link error

Following ERROR codes DO NOT allow engine to run :
11-12-19-30-41-50 and Er-1 to Er-4

Error code 11 allow engine to continue running only if fault appears after engine start.
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Hey Toby..if that sequence works, you should see if you can get a moderator to pin it in one of the topics so it will always be there. That is a handy-dandy thing to know!!
Ya I haven't tried it yet but hope some one does. There should be a way to adjust F/A ratio in the ECM also according to some other statements I read. This might be way over our heads though. I know it is mine and I'm sure if this is possible Yamy and Star officials don't want the average owner to now these things.:suspicious:
Is there another sensor that measures fuel ? I was thinking if the o2 was unplugged, how was the computer adding more fuel?

Sent from my HTC VLE_U using Tapatalk 4 Beta
That's the million dollar question and that's where the answer lies, and that's why nobody can get it right by trial and error and smelling the exaust and test running it unplugging this or that, because the variables are constantly changing. There are many sensors involved in the fuel processing information procedure in the entire EFI system. The 02 sends the final emissions readings, but you have the throttle position senor, load sensor, ambient air temp sensor, barometric pressure sensor, internal engine temp sensor, altitude sensor , ignition timing sensor, gear sensor, RPM sensor, coolant temp sensor etc. etc. Probably missed some but all these work hand and hand in sending ever changing info to the ECM(Engine Control Module) also know as the ECU, the brain that reads ALL this info and makes multiple changes every second to air fuel mixture.
The only guys that have ever got it perfectly tuned and never had a single problem with ANY aftermarket fuel possessor are the ones that have had their system professionally tested and individually mapped specific to their bike.
No disrespect intended, but I can't understand why anyone would think that they could do the work that was professionally engineered and designed to be done by a computer. I guess they just don't understand what all is involved here and I don't know why the companies selling these products don't tell them.
I did extensive research on the subject and came to the decision I wont do a stage 1 power up grade until I can afford all three mods, pipes, intake and fuel possessor plus have it professionally mapped.
I guess I should have posted this on one or all of the fuel possessor threads.
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I've been working on cars since I was a kid, both at home and in dealerships, and I do agree with what you said..to a point. There are a lot of factors that go into the final injector signal. The most critical,and dynamic (and that everyone plays with) is the O2 sensor(s), the MAF sensor, and the IAT sensor. All the other ones are relatively static. The throttle position sensor tells the ECU "I am at position "a", therefore I need "n" amount of fuel. Same with crank position, coolant temp sensor..etc. But the O2 sensor will hold reign over all the other ones, because that is the final one in the closed loop system. So regardless what the other sensors send to the ECU, if the O2 sensor thinks it's running too lean (or rich) it will tell the ECU to lengthen or shorten the injector pulse and the timing of the pulse. People either put a resistor in line with the IAT to which tells the ECU it's colder outside than it really is (and therefore the incoming air is denser) and needs to add fuel, or a resistor to the O2 which as everyone knows, tells the ECU it's running too lean and needs more fuel.

The tuners everyone puts on (myself included) compensate for larger amount of air coming through the intake. Stock ECU's can usually compensate satisfactorily up to a point. Aftermarket intakes and exhaust allow for more air intake/outflow, which "MAY" end up overwhelming the ECU, and cannot process a signal to compensate enough (depending on what you did, the stock ECU may be okay..you don't ALWAYS have to buy a tuner). All programming in an ECU is just a set of math functions, and if the results of the input do not fall within the criteria of a function set, the ECU will default to a parameter that will be less likely to hurt the engine (which is usually RUN RICH). The problem when this happens is premature fouling of plugs and O2 sensors due to excessive carbon build up...which then causes a crappy running engine in the long run (and if you have a catalytic converter, will also eventually plug it up).

So..my two cents for all the mod problems people have. Do your intake and exhaust mods first. If you have a significant problem compared to running stock, then spend the money on a tuner. When you unplug the O2 sensor or put in a resistor, you're making the engine run rich all the time, which is fine as long as you are aware of the long term effects as above. And when you do a mod...yes, you are changing what and how the bike was engineered to perform. So please do not ask for perfection from your mod.

It's like putting a radical camshaft in an engine, and then complaining because it doesn't idle nice....ain't gonna happen.

Sorry about the soapbox stance.
The problem with this theory is once you add a piggy-backed possessor to the ECU the 02 is no longer the final operational information sent to the ECU, it's the fuel possessor, which sends the info that fools the ECU into changing the A/F mix..
If I'm correct the aftermarket fuel possessor will send the same info from it's preset maps to the ECU no matter what you do to the 02. Not sure if the 02 still goes directly to the piggy-backed unit or to the ECU but don't think it matters much.
It was my understanding that, with the Cobra CVT, the only time the o2 sensor came into play was while the engine was in a steady state cruise mode - any other time the Cobra unit would be modifying the signal sent to the ECU (if necessary, of course).

Certainly wait to see what the outcome of the dealer's efforts are first...
"steady state cruise mode" is correct, and I beleive even with the stock setup the 02 only comes into play at idle and cruise. If I'm correct, it's main function has more to do with the emissions system than over all engine performance. When you hit the throttle all the other sensor take over, like throttle position and load sensors, and say, bubba wants to get going, richen up and inject more fuel.:nod:

And yes I too am waiting to hear the outcome of the OPs problem.
Unfortunately, some of us like the looks and basic performance of the bike, but aren't able to go around town at 50 mph in third gear all the time...so we mod :)))))) Unless you live where there are long open roads, and no cops, it's hard to ride aggressively all the time.
This I found to be a problem too. Much harder to deal with in stop and go traffic and stop lights etc.. But even though I have to putter around behind my wife at 20 and 30 mph in these mountains, the are now stop signs for 30 to 50 miles in any direction from my house, and then ther is only 2 or three stop signs and 2 lights. No big city 100 miles from my house, oh how I suffer.
So about the smoke in the exhaust... Lol I can only do what the dealer says since no one on the thread seem to getting anywhere. I appreciate the effort it's not a easy problem I'm having.
We didn't forget about you just got side tracked.
We all are waiting to hear what the dealer says.
Like I said my first thought were maybe one of the sensors went bad. What I didn't say was one thing that is rare but can happen at that low of miles after break-in is valves seat deep enough to cause too tight valve lash adjustment which could cause blow by and smoke. Didn't want to worry you unnecessarily.
I'm curious and it's not clear to me how you guy with 2 into 2 exhaust are collecting the 2 into 1 for the 02 bung to get a true reading off both cylinders? If not why?
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