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Smoke from exhaust

11557 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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Like Wayne said, hard to tell without really being there. It looks to me like a coolant leak somewhere (cracked case/head gasket). If it was fuel or oil, there would definitely be a smell, and it would tend to hang around in the air. Coolant would pretty much dissipate right away. Like Wayne said, check your fluid levels...might give you a hint.
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.
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!!
Ran worse with o2 unplugged
Was it still smoking with the O2 sensor unplugged?
I guess this goes back to what my Yamaha rep. said about switching out the pulley.
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.
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Joe, I can't & won't comment on how things perform on modified units. It's senseless to think any of these people have enough engineering knowledge to post anything.
There is not a week that goes by that I don't fix an ongoing issue with a bike, by getting it converted back to STOCK.
The bike was designed to NOT be chugged along - that's not the customer/bike target. This bike was designed to be ridden aggressively and kept in the higher rpm range, spending a minimum amount of time in first or second. The 13 STD & Tour has the personality it seems these riders would be better suited with. With aggressive styling come aggressive mapping and timing.
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.
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.
Yes, you are correct if you're using a fuel processor with preset maps (like the Fi200r). I've read posts where people are aware maps are for specific environments. I guess I was addressing more for the auto-tuner. Without the auto tuner, If the intake/exhaust upgrade flows more air, in the end of the process, the O2 sensor sends a signal that it is running too lean, but the ECU is unable to compensate, because the algorithm is programmed for a stock setup. Once the auto tuner is plugged into the system, it uses the ECU for info for acceleration measurements from MAP/MAF/IAT crank position, etc. and from the O2 sensor. but now when the O2 see's it's running , it's algorithms allow for changes to injection pulse that were beyond the ECU's capability. If you could find someone who was capable of reprogramming/flashing the ECU, it would do the same thing. So when someone unplugs the O2 sensor, the engine is getting whatever the default A/F ratio setting for "run rich". What I don't know is if it's the default from the auto-tuner, or from the ECU. If it's the ECU, then might as well toss the auto-tuner. Maybe someone can try that and see if there's a difference????
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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).
Correct, (and this should probably be moved to the tuner thread.) But if most everyone was complaining about surging/flat spots while cruising at certain speeds, and unplugging the O2 sensor made cruising better, then is the tuner actually necessary since disconnecting the O2 sensor will keep it running rich at cruise?
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?
I think that's the problem "they're" having Toby. They only have one o2 sensor to use.
Well, glad you got it fixed. Thanks for the update...and it sure made for some conversation :)
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