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Hey All, sitting enjoying the races at Road Atlanta. Came yesterday, rode 2 hours from the house. Coming down 85 the bike is "running" fine but has a severe lack of usual FJR power. Going up hills it was struggling to maintain speed. No passing power, otherwise running fine. Idle is off a little also. Checked battery leads and made sure they were good and tight. I also noticed this severe discoloration of both pipes. Gonna try to post pics but just in case it appears to be extreme heat...a bluish discoloration. It was also pouring most of the way here not sure if the water has anything to do with the discoloration. Anyway won't be heading back till tomorrow, is there anything else I can check while I'm here with minimal tools. (Camping at road atlanta) I can ride as is just wanted to get some opinions on what I can do before I head back. Also gave a dose of seafoam last night. The idle has improved today but still seems to be down on power. Thanks in advance.

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'04, what mileage? Power Commander? PAIR system still installed? Definitely getting too hot. Cats are ahead of the mufflers, so something is causing it. A few things to look at but not easily done on the road. Potentially cats getting plugged up can't handle all they are supposed to do. Rich fuel mixture causing cats to overheat? PAIR system reed valves crudded up holding them open slightly (allows oxygen/ambient air into exhaust). We typically think of lean conditions causing exhaust heat, but you'd have to observe upstream of the cats to confirm...
Perhaps lift the tank and see you have no vacuum leaks/hoses off, MAP sensor (black thing on top left of throttle bodies with connector and a vacuum hose) but it won't be a huge influence. O2 sensor could be failing but ensure it is plugged in. Potential TPS but I'd think you'd be complaining more of jerky throttle at certain throttle openings.
Two hours home... I'd almost say trailer it home to investigate the cats further.... if headers forward of the cats don't look like they were overly heated/discoloured, chances are the cats are the issue. Perhaps fill it with premium fuel (burns a wee bit cooler) and ride it such that it is running smooth, no lugging and don't do hard accels. That discolouration is going to be hard to remove.
Those are my ideas, I haven't really seen this before.

Sorry yah 04 with 19000 miles, no power commander. Completely stock....have to look at the pipes closer to the motor but from what I observed without looking hard at it was they also appear discolored. As to fuel, I ran 1 tank of high test stuff on the way down and I forgot to mention fuel milage is horrible. Had to fill with 20 miles left of a 120 mile trip. Refueled with mid grade and like said put a dose of seafoam. Conditions are definitely improved since yesterday but still a bit off when running to the ingles a mile away. Running fine, starts fine, and now idling smoothly but like said that typical pulling power still seems off. Could bad gas have caused this? Thanks!

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Interesting. Lower mileage, wondering why it would run rich..... bad gas is usually just got water in it, shouldn't cause your issue and it would stumble big as if you can't keep it runnning.... Seafoam won't hurt.
Injectors are just doing what they are told by the ECU... pulse duration a little big, but why. Try unplugging the O2 sensor? Connector on right side of the throttle bodies. How is the coolant temperature reading? I'll keep thinkin.......

Coolant temp was and has been fine. 2 bars which is normal. Only time I've seen 4 bars is in heavy traffic in July but not on this trip. Like I said it seems to be improving with seafoam....we r making a 5 - 10 mile trip this evening to meet some folks for dinner.....will see how it does. Maybe if it continues to improve I'll pour the rest of the seafoam in for another overnight soak. Took a 150 mile or so jaunt through the mountains as couple weeks ago with no issues. Oh took a peak further upstream of the cats and can't really tell of a major change in color. Thanks!

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Temps if normal (not cold) should mean not rich. If the headers aren't discoloured much upstream, then it's likely the rich mixture burning up in the cats = hot exhaust. The solution is finding the cause of the rich mixture. Seafoam is just cleaning up the fuel system, won't do much for rich/lean, but will take care of any water.

Check for obstructed air filter (mice nuggets). The ecu should compensate, but it may be packed. Would explain over rich and no power.

Thanks for the help! Rode it tonight to dinner, same as before better than yesterday but still off. Filled up and put the rest of the seafoam in......got 18 mpg. Buddy and I were talking about the airbox...will take a look at that before the races tomorrow. We were wondering if that could be a cause as I started storing her in my shed as opposed to the garage where she used to live. Thanks again for the insights. I will look into y'alls suggestions tomorrow.

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bungie4 wrote: ↑Sat Apr 06, 2019 9:18 pm Check for obstructed air filter (mice nuggets). The ecu should compensate, but it may be packed. Would explain over rich and no power.

Why didn't I think of that? Good suggestion.

raYzerman wrote: ↑Sun Apr 07, 2019 8:04 am

bungie4 wrote: ↑Sat Apr 06, 2019 9:18 pm Check for obstructed air filter (mice nuggets). The ecu should compensate, but it may be packed. Would explain over rich and no power.

Why didn't I think of that? Good suggestion.

18mpg would indicate an air box not full of shit. I would think. The ECU would be compensating in the other direction. Less air=less fuel=higher mpg, not less. Hey, I'm just an armchair quarterback here. If it was running that rich, I suspect you'd see some black smoke out the pipes, even with the cats.

and how the bloody hell do mice consistently FIND the air box like that. Jeebuz!

Well unfortunately you were correct....the airbox was clean...lifted the tank just for giggles and didn't see anything loose, hanging or otherwise remarkable. Checked the little rubber nipple things that you pull off for syncing and they were as they should be. Everything looked fine, no mice welcomed me at any point and no sign of any living where they shouldn't, soooo, I'm gonna baby it back this afternoon and come up with a plan b. May have to bring it to the man as I'm at a loss and its getting beyond my capabilities. Lol. Thanks again for all your help and suggestions. At least I can head back knowing I'm not cooking a whole family if mice!

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Bad coil pack or plug? Sending raw fuel into the pipes?

Carbon build up on the valves leaking raw fuel into the exhaust header?

When you get home, go into the DiAG screen and check for codes, even can access the functional table so you can check resistances and function of the Throttle Position Sensor (TBS), e.g.
If you have a service manual, go to sec. 8-57 and check Ambient Air Temperature sensor (wire is on top of airbox, connector in left cover beside air cleaner). Also check voltage output of the Intake Air Pressure sensor (aka Manifold Air Pressure or MAP sensor). Ensure the vacuum line and port are free of grunge and the vacuum line is clean.
Check the resistance of the TPS, as well as observing in DiAG that you don't have any big jumps especially around the 15-25% throttle opening as you slowly turn the throttle.
Check the oxygen sensor has a good connection, they don't usually fail outright.
Perhaps unplug and re-plug the ECU to refresh that bunch of connections as well.

My thoughts are with the low mileage, this hasn't a carbon build-up issue, of course a compression test would verify. If a coil failed, it would affect two cylinders and performance would be way down. Being we have discolouration on both sides, performance half assed OK, gas mileage sucks, my suspicion is it simply is getting too much fuel in every cylinder, but interesting nonetheless. If you pulled the plugs and all are black, that would confirm that.

Fuel pressure regulator?
Trying to think of something common.
Stuck injector wouldn't idle right.

Ok got home a while ago without a hitch. This whole thing just keeps getting goofier and goofier. About 25 miles or so headed home fuel mileage was still in the crapper. Then while on the highway I felt a surge. Then another. After the second one she was back to her old self again. I was able to pass and maintain speed uphill etc....the fuel mileage even went back to normal. Then................about 4 miles from the house she started to sputter again and has the loss of power problem again. Really strange.....so to recap......left Road Atlanta and she's sputtering, then she clears up for practically the whole ride home.....about 125 miles.......and now she sits in the garage a sputterer. Anyway that's it, i will try all the suggestions I can this week and see what I can see.

on edit....I do have a manual so I will check those things out too.

Eric, sorry that something is going weird on ya. All I know is I would camp out at Duane's or Griff's house if I had a problem like that and hope they took pity on me and not shoot me.

Following this with interest.

On again, off again, …. etc - broken wire? loose connection? Trying to think of the stupidly insignificant.

The DIAG should be revealing, I think.

No "check engine" light at any point?

Wasn't their somebody a few years back that pinched a wire reinstalling the clutch cover or something and exhibited really f'd up symptoms. Did you do anything before putting it in storage?

Yep, that was a pinched ignition pickup wire that got trapped during re-install of the right side timing cover.