WTF is this noise?

wfooshee · Jan 5, 2008

To be honest, I really don't know how long those plugs have been in there. I haven't pulled plugs since I bought the bike in June, because I haven't felt a need to.

The ride last Tuesday seems to have done something, as the idle roughness happened on that day, after the 220-mile ride. This didn't fade in, it happened.

That said, I rode a 45-mile loop this afternoon after dumping most of a pint of SeaFoam into a full tank. For now I'm going to treat this as a fueling condition, i.e. running very rich, based on my lousy mileage. After the ride, it does seem to idle better; left it running on the centerstand for about 5 minutes, and although there were some burbles, it was nothing like the sound bite in my first post of this thread.

When new plugs get put in, we'll see how #4 holds up.

If this is gonna require cyclinder head work, it's just gonna have to wait. I'm not covered by anything, and I can't afford serious shop time.

Added:

After the bike sat for a couple of hours, I went out and re-fired it. LOTS of backfiring while it sits at fast idle, which settled down as it warmed up. However, it still backfires on overrun nearly every time, and occasionally just holding revs. Didn't ride it again, supper's ready. Just wanted to report the backfiring, still seems to be a fueling issue.

03HiYoSilver · Jan 5, 2008

Wfooshee,

An additional side note, I had my CamChain tensioner replaced at 32k miles. It was making some more noise than usual according to the tech.

Is is possible your Cam Chain jumped a tooth and causing some these problems?

painman · Jan 6, 2008

Regardless of the issue, sounds like new cam chain and gears are in order with the number of miles. Might as well play it safe and don't let your engine self-destruct. I would also change out the old plug wires and install new ones while doing the plugs. Resistance in a plug wire can cause these symptoms and cause a plug to look like number 4. Lastly, run a can of injector cleaner through. Hope you get it straightend out. PM. <><

wfooshee · Jan 6, 2008

Haven't pulled any covers to check cam timing, but I would think that bad valve timing would be even worse than this. Under load, the motor seems perfect. Pulls strong, smooth, running at highway speed shows no misfire, exhaust note is clean. Overrun has a bit of popping, and the idle is rough, which I think could be accounted for by a rich injector and the fouled plug.

It's possible it's jumped a tooth, which would explain the sudden onset of the behavior, but from a couple of automotive experiences, I don't think the motor's running badly enough to show bad valve timing. One car jumped 2 teeth on a timing belt, and pulled very weakly, would not idle at all. Another car; well, now that I think about it, the other car was ignition timing, not cam timing. It had a distributor drive problem, and advanced the ignition timing almost 30 degrees! Very bad, but irrelevant to this problem.

Painman, injector cleaner is in the system now. Rode again after supper to pump some more through, total 80 miles today, and the idle is significantly better now than before, but I still have those little pops when coasting.

Fred W · Jan 6, 2008

But you still have not changed the plugs yet? And you have never personally changed the plugs so there is no telling how long they have been in there. I would not do anything else until you get those plugs out of the equation.

You mention this symptom came on suddenly. Generally that is the case with ignition problems.

As to running rich; you mentioned that you have a PCIII. At idle, most maps have zero fuel added at idle anyway, so loading a zero map would not really effect the mixture at idle. However, with the PC installed there is no feedback from the O2 sensor as it is disconnected. The system is constantly in "open loop" mode. Unless you have hooked the bike up to a dyno and created a custom map there is no telling what fuel/air ratio it will be running at. It is highly likely that this is the source of your carbonization.

There is also a CO offset value for each cylinder in the ECU firmware. It is possible that these values have been "adjusted" or are otherwise not right for some reason.

After you change the plugs, assuming the idle smooths out, you should then disconnect the PC3 completely (not just run a zero map) and hook up the O2 sensor and run it that way for a while to see what happens with the #4 plug. You'll also get to enjoy the lean surging again, (or for the first time, if you bought the bike with the PC3 installed).

Ari Rankum · Jan 6, 2008

wfooshee said:
I rode about 230 miles today, and when I got home, I stopped at a store. After restarting when I came out, the bike made a clunk while cranking, idled rough, and had this noise. Bike is idling in neutral, hands off the controls. Microphone is near the clutch cover.

Finally!!! A Tech question I can handle.

This one is easy peasy. Someone has replaced your Yammie inline four with a VDub flat four. Happy to help!!!!

wfooshee · Jan 6, 2008

Ari Rankum said:
wfooshee said:

I rode about 230 miles today, and when I got home, I stopped at a store. After restarting when I came out, the bike made a clunk while cranking, idled rough, and had this noise. Bike is idling in neutral, hands off the controls. Microphone is near the clutch cover.

Click to expand...

Finally!!! A Tech question I can handle.

This one is easy peasy. Someone has replaced your Yammie inline four with a VDub flat four. Happy to help!!!!

But they left the radiator in !!!??!?

burnergold2B · Jan 7, 2008

Have you done a throttle body sych. on it?

wfooshee · Jan 8, 2008

burnergold2B said:
Have you done a throttle body sych. on it?

Don't have the equipment, looking around for somebody that does. Not going to the dealer for it, no matter what.

I know it needs to be done, just haven't been able to.

As for the rest, I pulled the plugs again today, after riding a whole tank with SeaFoam in it, and #4 is cleaner than it was, much closer to the others. I went ahead and swapped it with #2 to see what happens.

Idle is smoother, and backfiring on overrun is reduced. I'm starting to think I sucked something in when I ran the tank down so low.

I've also, just to see, disconnected the PCIII and reconnected the O2 sensor, in other words I'm back to stock fuel management.

New plugs are coming, can't find them in town so I ordered some. (Plain, not iridium, for now.)

My panic from Tuesday night has subsided. I'm sure there's no mechanical problem. Bike is running much better after nearly 200 miles of cleaner being pumped through the fuel system. Idle is smoother, no dipping, although it's still not velvety smooth like it ought to be. Basically, the bike is as good as it was before the New year's Day ride.

Also, I'm not convinced that I might not have a bad PCIII. The improvement on disconnect was significant. Kind of strange, since the improvement when I first connected it was so significant.

03HiYoSilver · Jan 8, 2008

Wfooshee,

Good to hear things are improving for you. Are you running Top Tier Gas ie Chevron, BP?

I know when I had your similar problem and dropped off the New Iridium plugs...fouled them out getting it fixed... should have done what you did and held them out until the fix was complete.

FI sure does some strange problems... but great when it is running correctly.

Fred W · Jan 8, 2008

wfooshee said:
My panic from Tuesday night has subsided. I'm sure there's no mechanical problem. Bike is running much better after nearly 200 miles of cleaner being pumped through the fuel system. Idle is smoother, no dipping, although it's still not velvety smooth like it ought to be. Basically, the bike is as good as it was before the New year's Day ride.
Also, I'm not convinced that I might not have a bad PCIII. The improvement on disconnect was significant. Kind of strange, since the improvement when I first connected it was so significant.

Now that you are listening closely to the engine idle, don't get overly sensitive. Even an engine in good tune will have a little "burble" at idle. You do want to eliminate the misfiring that was present in the sound clip. But don't get hung up on getting "velvet smooth" sound.

Oh, and good news. It seems that your O2 sensor has not been fouled by running with it disconnected, or you would have not seen any improvement when plugged in.

FJRSTAR · Jan 8, 2008

wfooshee said:
burnergold2B said:

Have you done a throttle body sych. on it?

Click to expand...

As for the rest, I pulled the plugs again today, after riding a whole tank with SeaFoam in it, and #4 is cleaner than it was, much closer to the others. I went ahead and swapped it with #2 to see what happens.

Idle is smoother, and backfiring on overrun is reduced. I'm starting to think I sucked something in when I ran the tank down so low.

My panic from Tuesday night has subsided. I'm sure there's no mechanical problem. Bike is running much better after nearly 200 miles of cleaner being pumped through the fuel system. Idle is smoother, no dipping, although it's still not velvety smooth like it ought to be. Basically, the bike is as good as it was before the New year's Day ride.

Do you remember how many ounces of Seafoam (per tank fill-up) that you have been adding?

I'm fixing to add Seafoam to mine and change the plugs afterwards to iridiums and do the TBS. Wouldn't want to add too much.

wfooshee · Jan 8, 2008

Instructions on the can (was yours blank?

) said the pint treats 8 gallons, so I filled up and put 3/4 of the can into the tank.

And be prepared for some weird smells in the exhaust.

user 2024 · Jan 8, 2008

Reset the PC and reload your map. Also discussed in this forum is resetting the throttle position in the PC.

FJRSTAR · Jan 8, 2008

wfooshee said:
Instructions on the can (was yours blank? ) said the pint treats 8 gallons, so I filled up and put 3/4 of the can into the tank.
And be prepared for some weird smells in the exhaust.

It has the instructions on it but some people with experience with this stuff could conclude otherwise. Some people run it through the tank full multiple times then change their oil. I guess what I was looking for was reassurance.

Sorry I asked...just kidding.

wfooshee · Jan 8, 2008

I was having a little fun, too. But yeah, 3/4 of the can per tank would be my best-guess ratio.

I've not used it in the oil, but I did do the vacuum-hose application on one of my cars trying to get some pinging out. Helped a bit, but not what I'd hoped for. Maybe need to try it again.

WTF is this noise?

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