| Author | Message | ||
     Buelltours |
Hi folks, I am running against walls here: Thinking I knew a little about these bikes and how to do problem solving using Badweb threads, the most recent issues with a buddy's X1 has me dumbfounded: He bought the bike with a blown cam cover gasket which we replaced. Lined up the marks correctly, put the bike together, rode 80+miles and all seemed fine. The CEL light was on, ECM Spy said "temp sensor shorted to ground" but it didn't seem to matter until, up on the parkway, the bike started bogging down. The rear cylinder was noticeably cooler. I rode the bike home on 1 cylinder thinking all I had to do now was to swap the temp sensor, which I did next. The error code went away, but the bike still did not run right. ECM Spy showed the temp go up in idle, but when on a test ride, the rear cylinder seemed to stop running under load. A new O2 sensor followed (some Ford part) Didn't do anything. I checked the injectors, the squirts seem fine. I swapped the fuel pump thinking it may not make enough pressure, no change. Also a complete swap of the ignition coils plus wires (the spark plugs are new NGKs) did not change anything. ECM Spy is not reporting any trouble. After a TPS reset the bikes idles fine and the rear is running, building temperature. Under load however it stops. The intake seals seem fine, spray does not change the RPM. The ground cables (one on the frame and the big one to the swing arm) seem ok. I swapped the ECM with a Race Module, no difference. The bike only has 8K miles and does not seem abused. I have read many threads on non firing cylinders, but cannot find any more ideas... Am I missing something big? Do I not see the forest because all I see are trees? Thanks for any input!! PS: Since I have a few Buells, parts swapping is no problem. Let me know if you have any ideas.... Thanks!! | ||
| Oldog |
A: rear cyl compression? B: condition of wiring to injector and coil C: do you have access to a spare ecm? after confirming compression and static timing on rear cylinder ( valve & piston movement ) check condition of wiring to coils and injectors runs at idle, not at power, read cylinder drops out. swap injectors front to back ( injector failing under load ? ) swap coil with another if avail ( coil / wire failing under load ) swap ecm to see if its failing under load. please keep us posted IHTH | ||
| Buellistic |
Check the REAR EXHAUST HEADER GASKET, if bad replace it with the -98 part number EXHAUST GASKET ... EXHAUST SYSTEM ASSEMBLY Class 101, just PM me for a copy ... | ||
| Buelltours |
I did not check compression yet. That may be a good lead. The wiring on the injector seemed fine, I diagnosed both injectors with both connectors and saw the same result when cycling with ECM Spy. The Race Module I tried did not change any behavior of the bike, so I rule out the ECM being faulty. Static timing also revealed no issues: Going by the procedure using ECM Spy, I am seeing the timing mark in the middle of the window when "0" changes to "5". Buellistic, how can the exhaust gasket have anything to do with it? I did take off the header a few times (change cam gasket) but would not expect the cylinder to completely die under load... I will PM you for your 101 classes though... Thanks guys, I am going to check the compression next.... | ||
| Fullauto |
Change the spark plug. You've done everything else. You never know. | ||
| Mcelhaney14 |
I had an issue of no spark on the rear cylinder awhile ago. I tried swapping out everything to no avail, cam sensor, coil, spark plug, plug wire etc. Finally, for a guess, I switch the starter and ignition relay in the fuse box and then it worked again. Hope it helps. Bill | ||
| Oldog |
tours static tests good failing under load is a lot harder to find. you are loosing fuel of fire ecm/connectors/wires/devices moving the coil or injector check the valve operation for the rear cyl confirm that they are moving the full distance. btw check the wiring with a meter end to end if nothing else turns up | ||
| Buellmanmike |
I chased a no fire rear cylinder for well a long time! Tried 2 separate carbs on it. Ultimately it was Boost Lab in Tampa, which fixed my bike. $20.each to clean injectors, worth every penny!!! | ||
| Buelltours |
ok, had time finally to continue troubleshooting: tried the relais swap, checked compression (120 both cyl), checked the push rods and valve action. The injector squirts look good and the front/aft swap did not produce any difference. Static timing is good, all sensors working. Advanced and retarded timing a bit, the check engine light came on. Currently have no trouble codes. The rear cylinder is dragging its feet.... I am short before getting into the wires. I don't have a breakout box. Is there any recommendation on how to best approach this? I never had such trouble before... | ||
| Akbuell |
Sounds like it could be a 'heat' failure in the electrical system. As an appliance runs, the electricity causes the part to heat up. So, perhaps, especially given all of the things you have already tried, a close look at the cam position sensor might be in order. Runs fine for a while, then continuous running causes a partial failure, sending a corrupted signal to the ECM. Hope this helps, Dave | ||
| Akbuell |
Just so you know what I am hearing - the rear cyl runs at first start up, then drops off after a period of time. Might do the check with Reepicheep about using a scope to check the CPS. In the interim, perhaps taking the cover off the CPS, start the bike to confirm both cyls running, then shut it off. Heat the CPS with a hair dryer or heat gun, then start it again. If the rear cyl doesn't fire, that could show where the problem is. Hope this helps, Dave | ||
| Buelltours |
Dave, thanks a lot for your input. Most recently the bike behaves as follow: Upon start (cold) the front cylinder is warming up quickly, the rear cylinder only comes up to about 50degrees C. The bikes idles at 1000 rpm, however when you blip the throttle, there is a hesitation for 1s, then the bike revs up. It doesn't sound right though and I haven't tried to ride it in a while now. Today we checked continuous sparking. There is no problem. The plugs are wet, so there is fuel. The cam sensor seems fine. Then we proceeded to check mechanicals again, checked the cams and found a bent exhaust push rod on the front cylinder. We exchanged all push rods, checked the valves for straightness (all fine). What could have happened to end up with a bent pushrod? We are scratching our heads.... :-) | ||
| Akbuell |
PM replied to.  | ||
| Akbuell |
In re-rereading your original post, would do to check over your work concerning the cam cover gasket repair. Make sure the wires from the CPS haven't been pinched somewhere at reassembly. Confirm the plug-in from the CPS to the wiring harness is secure, and all of the pins are seated correctly. Did something get caught when putting the pulley cover back on? If tie wraps were used, is one too tight? Hope this helps, Dave | ||
| Akbuell |
PM forwarded . . . . If I got the addy right . . . | ||
| Mebuellx1 |
Buelltours, did the problem get resolved? If not, one thing I feel I should mention is just make sure the trigger rotor is not actually hitting the cam position sensor. If you had to "pry" that trigger rotor off the shaft when you were taking the rotor and cam sensor off, it could have bent that rotor just enough to actually make contact with the sensor. If one of the rotor tabs is rubbing on the sensor, it will eventually heat up enough so the cam sensor will not work until it cools down. Not that I had this happen to me or anything like that. | ||
| Akbuell |
Situation update: Did a careful inspection of the ign system, and found no real issues. Since the cam cover had been off, removed the pulley cover and wiggled stuff around in there. Moving the CPS harness cured the problem, for about 15 sec. Pulled the harness apart, and found the wires were not happy. Installed a replacement CPS, and the bike was better, but still not happy. Being more confident in the ign, we checked the injectors, and found a torn O ring on the rear one. Replaced that, and just since we were in there swapped them front for rear. The problem followed, with the front cyl not running well. So it seems the CPS was sending a 'corrupted' signal to the ECU, causing spark issues. At the same time, or possibly because of the 'corrupted' signal, the rear injector became unhappy. In any case, new injectors and a careful reassembly should result in a happy motorcycle. | ||
| Buelltours |
Thanks a lot for your assistance in the troubleshooting, Dave! And I promise that I get me some dielectric grease! Long live the X1 :-) |
