| Author | Message | ||
     Kodas |
My S3 buell cranks but refuses to start.  Its fuel injected (1999) and I've trouble shot the thing via the Buell shop manual flowcharts for "Engine Cranks But Will Not Start" section. There are no trouble codes and the computer seems to think everything is OK (the indicator light goes out and doesn't blink). Chasing the charts the only thing wrong seems to be no signal off terminal A & C (yellow/blue & blue/orange wire off the coil connector [83] (ergo no spark from the coil). Terminal B (gray wire) is getting twelve volts and all other ignition circuits are powered up. I've tested A & C terminals with a test light that is connected to +12 volts in series to the terminal (A front cylinder or C the rear) and the light doesn't flash when cranking the engine. I've also tested the source pins 6 & 7 (black connector) on the ECM. Still no signal. The cam position sensor (CMP)is sending a 0-5 volt signal on pins 3 & 8 (green/white & black) off CMP connector 14 when cranked, as it should. Pins 3 & 8 (signal from CMP) off the (gray connector) ECM also tests fine for resistance. All the other related resistances between the connectors and the ECM also test fine. Are there any other conditions that would cause the ECM not to send a signal to the coil? PS. On a lark I replaced the CMP sender (most likely to fail) and subsituted another ECM but this changed nothing. Help!  | ||
| 99x1 |
"My S3 buell cranks but refuses to start." The bank angle sensor shuts off the ignition, but also shuts off the fuel - it might not post a code (according to the chart -> No codes, then has the scanalyzer check BAS Mode = RUN). Maybe try unplugging the BAS and see if it posts a code? Good Luck; John | ||
| Kodas |
Tanx 99x1 - John. Unhappily the BAS seems OK - there is 12 volts to the coil, fuel pump and rest of ignition, etc. Ruling out the BAS for bad behavior.  Oddly enough I've shaken, leaned and turned upside the BAS and it didn't kill the power as expected. This was years ago but I didn't replace the part as it tested fine out of the circuit, and at the time the bike ran perfectly. I mentioned this to the dealer and I think they replaced the part at a regular service interval. Have to check my receipts... edited by kodas on June 28, 2003 | ||
| 99x1 |
"Unhappily the BAS seems OK - there is 12 volts to the coil, fuel pump and rest of ignition..." The ECM turns the on or off the ground (negative) connections to both the pump and the coil - the +12 will be there even if the pump/coil is off (the negative is software controlled). Since you have replaced the ECM, other then not getting a pulse from the CMP, AFAIK, the BAS is only other item that will tell it not to run. And since it seemed to act strange at one time..... | ||
| 99x1 |
Also, the ignition has it's own ground connection (shown as IGN GND on the wiring diagram). Pin 11 on the black ECM connector is called "System Ground B (coil)" - check it is making a good connection to ground. John edited by 99x1 on June 28, 2003 | ||
| Kodas |
Good Point! I can hear the fuel pump run when I flip on the engine switch so I assumed the +12V meant everything was cool. You comment that the ECM uses the ground to turn systems on and off has got me thinking. Don't know why it didn't dawn on me - thats how the coil signal works, why not everything else? I'll check that BAS, Pin 11 too. Good stuff! Thanx very much. Your comments have helped a great deal. It always seems to be a bad connection... Alright its late, I'll bite. What's the acronym AFAIK stand for?  | ||
| 99x1 |
AFAIK: As Far As I Know | ||
| Kodas |
Ha. And I was going to spend the day RTFM for a part number. Tanx again for the help John. | ||
| Kodas |
99x1 -You are a gentleman & a scholar! The voltages to the BAS connector were within spec but the signal back to the ECM was 3.78V, well outside the .6-1.1V range listed in the workshop manual. Pulled the BAS and finally got an error code 44. The the bike started and ran well. Even with a new ECM that hasn't had the TPS calibrated. Tanx so much!!! I owe ya a beer - at the very least.  Just for reference what's the best way to test a ground signal created by the ECM? edited by kodas on June 30, 2003 | ||
| 99x1 |
"the best way to test a ground signal created by the ECM?" Put the positive lead of your voltmeter on the battery positive terminal and the negative lead on the point being tested. When the point is switched to ground by the ECM, the meter will read battery voltage. (This is called an "active low output" in computer terms, while a switched positive line is called an "active high output".) | ||
| Kodas |
Ah. That is what I thought. Swear I was getting an "active low output" when I tested the coil ground... Who cares? Its running!!!! And again thank you. | ||
| Kahuna |
some help would be appreciated. i picked up some NGK plugs today and when i came home, i realized they dont have the end caps on them? can i buy these caps? or are they a waste now? thanks. | ||
| Bykergeek |
Does anyone know if Buells or any other motorcycles use the OBD2 diagnostic interfaces which are on all cars made since 1996 ? | ||
| Cartman |
I have a '99 X1 and the spark plugs get severely carbon fouled in about a half mile to the point where it causes my engine to sputter and misfire when under any load at all. Both spark plugs are identical. Any ideas anyone? Thanks.  | ||
| Kodas |
Cartman, here's the standard list: Incorrect plugs Piston rings badly worn or broken Fuel mixture to rich Valve stem seals worn or damaged Valve guide badly worn. If your riding only a half mile and fouling, sounds like guides or rings. Is the bike consuming lots of oil or smoking? | ||
| Cartman |
Doesn't smoke, bottom end only has about 2500 miles on it. I can't tell if it is consuming lots of oil because I can't run it long enough to burn oil. Could the O2 sensor be making me run extremely rich? What other sensors could be affecting this. Thanks. | ||
| Kodas |
How would you characterize the fouling? Wet black shiny deposit? - Worn pistons, valves, guides or seals, weak battery, faulty ignition. Dry, fluffy or sooty black deposit? - Too rich, engine idling for excessive periods, or enrichener usage for extended periods. Light brown, glassy deposit? - Overheated sparkplug, fuel too lean, hot running engine, valves not seating or improper ignition timing. Maybe the 02 sensor, but this extreme fouling suggests other problems... Possibly with that 'new bottom end'. A simple compression test will disprove ring or valve issues. | ||
| Cartman |
It's dry, sooty black deposit. Very thick. It doesn't look like there is any oil on the plugs. I have a compression gauge but it only has fittings for cars. Can I buy and adapter so it will screw into the skinnier plug holes on the Buell? | ||
| Kodas |
Cartman, most gauges come with a set of at least two fittings to handle the vast majority of plugs out there...Though I've never actually checked if my gauge and screw in adapters fit my Buell. Odds are you can find/borrow one that works!  | ||
| Kodas |
Oh yeah, your description of a sooty black deposit certainly rings of an extremely rich mixture. Now I'm leaning toward the 02 sensor not functioning properly. How's the bike running at idle and below approx 2500 rpm, or full throttle? These are times when the bike is in open loop mode and doesn't use the O2 sensor. | ||
| Kodas |
Cartman, there's an excellent explanation of how to check your O2 sensor in the Engine - Carburetion, Fuel Injection section of the forum. Check out 99x1 responses. He's good and supplied pictures too! | ||
| Cartman |
Idle is normal. I don't remember specific RPMS but yeah it probably starts around 2500. If it is the O2 sensor what does one cost? Thanks for all your help. | ||
| 99x1 |
If the fuel injection "thinks" your engine is cold, it will run the engine rich (like choke on a carb). If the head temperature sensor or intake air sensor is not working properly it would run rich. The resistance of these could be checked. The O2 sensor can also cause problems throughout the RPM range, as it compensates for altitude (or fuel quality) by changing the injection map (I think..) outside the closed loop range based on values from the closed loop. (AFV - Adaptive Fuel Value). It is rumoured the AFV can get out of sync (like if you run out of fuel), and may need to be reset? Good Luck. | ||
| Mbsween |
Cartman, like 99x1 said, check that engine temp sensor. My 2001 did alomst the same thing as your except that it took between 10 - 15 miles. Its easy to replace and costs about 30.00. The hardest part is finding someone who has one is stock. Try Dave at IOWA hd, he'll find one for you. Good luck Matt | ||
| Kodas |
These guys are good! I'm not aware of the 02 sensor causing issues when the bike in in open loop mode but ya learn something new everyday! Here's a little tidbit from the S3 Files FAQ that discusses how to reset the AFV: "Ride the motorcycle in closed loop operation (2500-3500 rpm, approximately 40-60 m.p.h. in 4th or 5th gear with engine under load) consistently for 2-3 minutes. This allows the ECM to learn a new Adaptive Fuel Value (AFV)." Here's another short blurb from CafeRacers that defines Adaptive Fuel Value (AFV) for what its worth... Anyway tanx 99x1 and Mbsween sounds like Cartman's issue is nailed - the ET sensor! | ||
| Seatonii |
O2 operation as it relates to "closed loop" and "open loop" operation, this information is coming from the automotive side of the business and I would assume that it is the same for motorcycles. The term "closed loop" means that the ECM using the information from the O2 sensor to adjust the base cal that inside the ECM for the current running condition The term "open loop" means that the ECM is not correcting the base cal in the ECM it is just running off of the base cal with no correction from the O2 sensor at all. I think this system is that same as ours in respect to when the ECM goes into "closed" and "open loop". The ECM will go into "closed loop" as long as the O2 sensor is hot enough and it has sufficient cross counts, the O2 sensor needs to be hot to have sufficient cross counts. As soon as this happens the ECM will go into closed loop. When the O2 sensor stays on one side of .450 mv for a period of time, like WOT, the ECM will not see enough cross counts and then it will go into open loop and ignore the O2 reading because it is not accurate. The type of O2 sensor we use can not tell accurate air fuel ratio at any point But 14.7 to 1. The O2 sensor just tells it is richer and 14.7 to 1 or leaner than 14.7 to 1. So, if the O2 is not actively bouncing from to one side or the other, above or below .450 mv, then it is not sure what the air fuel ratio is, with any great accuracy, so the ECM goes back to a base cal. DWIGHT | ||
| Bartimus |
I've got a '95 S2 that's been a great runner. It just recently started giving me trouble. While riding, the bike will suddenly loose power, and drop to idle. While doing this, the tach will jump around from 1000 to 8000 rpm even though the engine is barely idling. I give it gas and it tries to run up but sounds like it's only one cylinder. If I turn the bike off and wait a minute and turn it back on, it runs fine. This has been happening for about two weeks intermittantly and is happening more often. Last night it happened for the first time at night. When it happened, my lights and gauge lights dimmed, until it started running right again. I'm not sure if this is a short, an electronic problem, an ignition problem, or if my plugs could be causing a problem. I've got 144,000 miles on the bike, with about 8000 on a new top end that has been blowing oil on the front cylinder. I clean the front plug about every 500 miles and wonder if it has anything to do with this. It really seemed like the problem was the ignition, until I saw the lights dimming last night. Now I'm not sure. The bike is carburated, has stock ignition. Any ideas anyone? | ||
| Monsta |
Anyone have a clue as to why a fuel pump would not come on when the ignition is turned on?? I have spark, plugs are fine, just not getting any fuel!! I think it might be the Bank Angle Sensor, but I can not find the damn thing.... Oh by the way its a 00 X1... Jesse | ||
| 99x1 |
AFAIK, if the Bank Angle Sensor (BAS) is at fault, the pump will still run for a short time when the key is first turned on. The pump is controlled by the ECM, pull both ECM connectors and then short pin 3 (Bn/Y) on the removed black connector to ground - this should start the pump (which will run until it pressurizes). Does the Engine lamp light at Key On? (ECM power?). Do any fault codes flash on the Engine lamp? Disconnect the BAS (left side under tail section), and you may get a engine code. The BAS should output ~0.65 <-> 1.1 volts, it could be bypassed using a couple of diodes and a resistor. Good Luck.... | ||
| 99x1 |
I checked what I posted above - with both ECM connectors off, a paper clip from Pin 2 (Black - which goes to frame ground) to Pin 3 (Brown with Yellow Stripe which goes to pump) on the black ECM connector causes the fuel pump to run.  |
