| Author | Message | ||
     Shadowracerx1 |
I have a 1250 engine I put together last year with xb9 pistons. At the end of the riding season the bike started running bad. I checked for air leaks and wiring and found no problems. I reflashed the ECM to an earlier tune. I started the bike and the front cylinder wasn't firing. Since then I've swapped spark plugs (the front plug was fouled, plug wires and cam sensor. So what happens now is it will start, warm up idle but bogs in the higher RPM range... then the plugs foul again (more front than back). I'm using megaviewer to try to smooth this out but I'm at a loss. I''m trying to avoid throwing money at it before I have a better idea what's going on. Any insight would be appreciated. Thanx | ||
| Akbuell |
If it ran fine before, and nothing has been changed, then I suspect the fuel injectors have begun to leak or are clogged and spraying fuel, instead of a mist. There is a procedure in the service manual to check for leaking injectors. Hope this helps, Dave | ||
| Nillaice |
did you upgrade the injectors when you did the 1250 kit ? or just change the fuel maps so that the OEM injectors were open for a longer cycle? | ||
| Shadowracerx1 |
I upgraded the injectors to Siemens Deka 60LB. | ||
| Nillaice |
did you leave a rag in the velocity stack the last time you had the air box off? it happens to the best of us ... | ||
| Shadowracerx1 |
I did that Once...  I've been using a torch to "unfoul" the plugs. I grabbed some new ones today and I'll throw those in. Could this be a symptom of the ECM going bad? | ||
| Natexlh1000 |
I would doubt that the ECM would go bad like that. Since it's the front jug that's doing it, it would have to be something that only affects the front jug. Like one of the injectors drooling or the ignition coil being half-dead. Bear in mind the ignition coils on these is actually two independent coils in one box. I would suggest chasing the injector theory first. | ||
| Shadowracerx1 |
I had a spare coil (actually I have a spare everything just about) and tried swapping it. I'll check the manual for injector testing options. To be clear... both cylinders are fouling... seems more fouling is happening to the front. (Message edited by shadow-racerx1 on June 16, 2016) | ||
| Akbuell |
'08 manual - Sec 4-14. The very last paragraph. | ||
| Shadowracerx1 |
My bike is an 03. The 08s had several cool things added for this kind of stuff that aren't on the earlier models (I've heard they have a way of cleaning fouled plugs even.) | ||
| Natexlh1000 |
well if they are both fouling up, it could be a bad engine temperature sensor telling the bike to run crazy rich. (like choke stuck shut) | ||
| Akbuell |
S'OK. My '01 tuber manual has a nearly identical check to the '08 manual. It is listed under the throttle body section in both manuals. Short version is to remove stuff you need to remove so you can look into the intake manifold with the throttle open. Turn the key on, then the stop/run switch. On for 2 sec, off for 2 sec, repeat 5 times. Look in the manifold for signs of raw fuel. The only real difference between the 2 is tuber hold the throttle open, XB the throttle is closed. Don't know about your '03. Throttle closed, maybe? Dave | ||
| Natexlh1000 |
Yeah that makes sense. Turning it on pressurizes the fuel line abut not starting the engine up leaves the injectors closed. If any gets out, it's bad. I did the same to find out which of my Dodge's 8 squirters it was except I had to pull them all out to see them. | ||
| Shadowracerx1 |
Thanx. I"ll try that. ECMSpy is showing expected temperature... but that's not to say it hasn't gone out of whack. (Message edited by shadow-racerx1 on June 17, 2016) | ||
| Shadowracerx1 |
Injectors tested fine. | ||
| Shadowracerx1 |
ECMSpy shows my AFV to be over 140%. That can't be right can it? Everytime I VE analyze, megaviewer adds fuel. What are the chances my spanking new O2 sensor is the culprit? How does one test the temp sensor? | ||
| Shadowracerx1 |
Resetting AFV has me running well enough to start tuning. | ||
| Natexlh1000 |
If it tunes itself wrong again, you can blame the oxygen sensor. If the sensor was reporting too much oxygen, the computer would add more til it smells right. | ||
| Shadowracerx1 |
Now it's down to 84% *shrug* I'll keep an eye on it. | ||
| Natexlh1000 |
Well that's weird. I can understand if it fattens itself up again or if it leaves itself alone but not going the opposite way! Other than the AFV, is it running OK? | ||
| Shadowracerx1 |
Yeah... I'm up to the 7th version of my tune map. Idle is good, revs to the red line with no hiccups. Need to iron out some niggles... |
