| Author | Message | ||
     Natexlh1000 |
I looked down the throat as it was idling and it was popping flames out of under the butterfly. Does this sound familiar to anyone? It's not throwing a code or anything. | ||
| Sagehawk |
Compression n leak down test this weekend? | ||
| Mark_weiss |
Fire in the intake? There are not an awful lot of things that cause that. A sticking intake valve? That would show with a compression test. Is it backfiring loudly or just minor popping? Regular or intermittent. Ignition timing issues? It is hard for the timing to be out of sync, but a failing crankshaft pos. sensor could cause this. Leaking injector? This would be pretty rare. You've checked battery connections and grounds? Make and break circuits can cause all manner of issues. | ||
| Natexlh1000 |
Just running like timing is wrong or something. I rolled the dice and pulled the ECU. I saw the connectors have been rubbing the seatpan despite my killing back the area of the seat that was touching. I'll bring it to work and peep it out under a microscope/reflow the connectors. I'll post if I see anything. | ||
| Natexlh1000 |
Didn't really see much in the way of a "smoking gun" but I went through the motions of resoldering the connector pins. I'll try it out tonight and if it runs right, I'll epoxy it shut. | ||
| Etennuly |
What gas do you run? Is there normally oil in the air box base? Can you see carbon build up in the bottom of the intake? If nothing else has failed and this is your only symptom it could be a chunk of carbon stuck on the intake valve seat. I had the intake off from mine at 30,000 and the amount of carbon baked on sludge was amazing. | ||
| Natexlh1000 |
Having the intake valve not closing all the way due to a booger is not really something I had thought of. The gas I run is always %10 garbage That's what you can get around here. And yes my airbox looks crappy as hell from the breather. | ||
| Natexlh1000 |
Well it's not worse now. Of course it's not better either. I'm thinking it's the timing sensor. If I hold it at 2000, it sputters worse. If I hold it to 4000, I can still hear it a little. Time to dig out the ole' oscilloscope. | ||
| Hughlysses |
I don't think I've seen any reports of timing sensor failures on the 08-up engines, but it's certainly possible. Let us know what you find. | ||
| Reepicheep |
You can hook up the scope right at the ECM with some stiff wires through the back of the connector. Easy Peasy if you have a scope. | ||
| Natexlh1000 |
I put a little more time into it last night but couldn't find a friggin' power cable for my old scope. Did some research on the sensor in question too. I was perplexed as it only has two wires coming out and the schematic shows neither as +5V or ground. It's just a guitar pickup! No semiconductors in there at all. Anyways, I hope to scope it out tonight. It doesn't seem to have anything wrong with the intake valve sealing as it cranks over with no odd sounds from the throttle body. The failure mode is odd too. It starts right up and runs fine. Then as it settles the idle speed down, it starts to run crappy. You can hear the idle port make more and more noise as it's trying to maintain speed. It may very well be the ECU itself but I want to be sure it's not just some dumb other thing first. | ||
| Reepicheep |
I believe there is a hall effect sensor and a magnet built into the cam position sensor. At least there was on the 07 and earlier ones. My Mini wheel speed sensors clearly have a cam position sensor, but they also don't appear to have a magnet in there. The only thing I can figure about how they work is that the bearing or some other rotating piece in the hub must be magnetized. | ||
| Hughlysses |
Bill- his bike is an 08 ( just like your new "new" Uly) ; it has a sensor on the front of the crankcase that is triggered by "notches" on one of the flywheels. | ||
| Natexlh1000 |
Well I poked the scope on the back of the ECU since it's still depotted. The signal looks just fine to me. Clean sine wave with two peaks missing on regular intervals. I was continuing to poke it looking for any other interesting signals and it gradually occurred to me that the dumb thing was running right. Great. I "fixed it". I am leaning towards ECU itself right now. Since I was going to buy a race ECU anyways, I guess I am going that way. Hopefully, I have enough in the budget in this pay period for a hit. | ||
| Reepicheep |
Cool. A sine wave huh? That's interesting. The hall effect sensors used pre 08 put out a square wave. It's a true / false, not an analog curve. Don't trust your test until you can repeat it with the bike running wrong. When my CPS sensor was dying, it would work fine (and the square wave would look fine) while the bike was running right, and then when the sensor got to a particular temp (or phase of the moon, or alien mind control, who knows) it would start dropping out some but not all pulses as the timing cup went by it. Like you say though, if you want the "run right reasonable emissions" ECU instead of the "run reasonable and meet some emissions target made by people who don't understand the problem and don't have to live with the solutions", then that's a common failure part and an easy diagnostic. Buy doodad you wanted anyway, install doodad you wanted anyway, see if it solves other problem. | ||
| Natexlh1000 |
It was running wrong when I was measuring the waves. Sputtering and coughing like real champ. I saw nothing unusual in the waves at the same time. I "repotted" the ECU for now so I can reinstall it. I'll get a EBR racing ECU when funds allow. | ||
| Natexlh1000 |
bump. Just ordered it. will know sometime next week either way. | ||
| Phelan |
IF that doesn't fix your problem, I have an 08-10 CPS for $30+shipping, or if you just want a spare. | ||
| Natexlh1000 |
Seems to be fixed!TPS and it started right up and settled into a stable fast idle of 1500 RPM. When it went down, I took it for a quick spin around a parking lot. Runs great with no issues. The new ECU has odd fan logic that will take a while to get used to I guess. | ||
| Reepicheep |
I notice the odd fan logic difference between my 08 and my 07 as well. The 08 seems to run the fan as often as possible when it thinks I won't hear it. I'll come costing to a stop and hear the fan kick off so I don't have to listen to it (which is clever). | ||
| Natexlh1000 |
Rode it to work this morning. Like a new bike! Behaves much more like my X1. Me likey! |
