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Discussion Starter #1
Hello,

I have been having a somewhat of an intermittent problem with my 99 Blackbird US model.

Symptom: The bike occasionally goes in to a sort of “funk” on startup and sometimes goes away and sometimes it doesn’t.

First time: started it up. Waited for idle to come down to 1100, before that happened it “stumbled” and starting running rich or as if it was on 3 cylinders. I needed to get home so I rode it anyways… As I hit second gear, the bike came back to life! And off we went. I did not see the problem again for a month or so.

Second time: the symptom came about in the same way, however it never come out of this running rich state...I then proceeded to search the forums; my first thought was the fuel pressure regulator. I replaced it. While priming the fuel pump I noticed a small fuel leak in the fuel line, I replaced that. No change, every time I started the bike I had the same issue.
My next thought was it has to be electrical! So I changed the reg-rec and it tested bad. I then replaced it with a shingiden regulator. Started the bike, it sounded better but not “right”. I then go to adjust the idle, I took it up to 3k then back down to 1k and then ended at 1100. Suddenly the bike “stumbled” and came Alive like nothing happened! The RPMs shot up to 3.5k on idle on its own.. I idled it back to 1100, all is good...YAY!

I rode the bike for about two weeks and about 200 miles on it with no issues.

Third time. It “stumbled” on warm up and went right back to this “funk” and won’t return to normal.

I am at a loss right now on the issue…I think about the wax unit or the throttle position sensor or a loose wire. But I am still unsure of where to go and I keep in essence throwing money at the problem….suggestions?
 

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Hello Brother from Florida with a 99.
Got one of them to. Search Loom Fix on this site and your problem will be solved.

I would list the link for ya but just ate and had A adult beverage....camping happy now :)
get that soldering iron out

STex, out
 

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Before you get out the soldering iron, verify the ECM connections are clean and the unit is strapped down.

Important, always disconnect the battery b4 messing around with computer connections.
 

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Discussion Starter #5
Thanks all.

I will be doing the loom fix this weekend. My ecu has been strapped down. When it wasn't months ago it made the bike jumpy and jolt when it got jostled around; I zip tied it down and all good on that area since; I will double check those connections as well.

Thanks,
Nick
 

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If it feels like it's "running on three cylinders" (or less), an easy way to check firing cylinders is to check the exhaust header pipe temps. No fancy tech is required really, just a hand/finger near the head pipes will maybe tell the tale.

When I've experience the "sudden loss of power" (not on my xx, but...) I traced it back to loose high tension leads (spark plug wires) connections or poor contact between the coils and the spark plug wires. One machine in particular would exhibit this while riding in the rain, a bit of water would cause the spark plug boots (not stock plug wires mind you) to slip just "that much" off the spark plug tower/s.

Some what related: When I purchased my XX the bolts/nuts/spacers required to hold the coils to the airbox housing were missing, so I remedied that situation with new hardware. That said, the XX has never missed a beat really. Mine is a carb model btw.


T.
 

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If it feels like it's "running on three cylinders" (or less), an easy way to check firing cylinders is to check the exhaust header pipe temps. No fancy tech is required really, just a hand/finger near the head pipes will maybe tell the tale.
Spray some water on the pipes, one at the time. That will tell you which one running cold and save your fingers.
 

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Discussion Starter #12
I completed the loom fix. Checked wiring on ecu. No change. At least the loom fix is done. Back to square one. Thinking about pulling the plugs next.
 

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Sounds like an intermittent misfire. Pull plugs and they will give you a better picture of things. Ignition problem most likely e.g. plug, boot, wire, coil.
 

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Discussion Starter #14
Update: Pulled the plugs, they were a bit wet with petrol. checked spark on all, great. re- assembled, started, No difference.
Then I pulled the PCM checked wiring, I found one frayed wire (exhaust valve, Orange with black stripe.?) I replaced the section and re taped the harness. Then placed a new battery in it.
Started her up and rpms were all over the place for about 10 seconds and it has been running fine since.

I should have started it in between wiring issues and battery replacement to narrow it down. Either way she is currently alive and well again.

-Nick
 

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Nk
The scattered Rpm on the initial were probably the system resetting to the correct input pulse. Double check your repair and make sure it's as oil and water proof as possible and you should be good to go.
 

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Discussion Starter #16
The saga continues...

Thee bike ran great for 4.5 tanks of gas, riding nearly daily with no issues. Then after a 10 minute ride on deceleration I felt it go in to its "funk", and it came back out a couple seconds later. Then again while passing at 80mph...complete lack of power.. then it corrected again. The next day on warm-up it went back to running rich...SMH. Checked wiring, cpu, and battery, no change.



...If anyone has a clue, please help. https://youtu.be/av02zx8q-bk

Regards,
Nick
 

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Nick, when you first turn on the ignition does the FI light illuminate for a few secs then go out? (like its supposed to)
 

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sounds like its running on two cylinders to me , cold start then check ex pipes temp just tap with your finger bet 2 are not so hot :)
 

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When I got my 99 I replaced the fuel pressure regulator with the upgraded fpr from 2001+. Don't remember all the specs but it pushes more fuel than the stock one that the 99 came with. While i didnt have all the problems you are having it did run sludgish. I replaced it with the fpr for the 99 and my bike ran better. Since your plugs are wet it could not hurt to give it a try.
 

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Discussion Starter #20
Verdict... Two cylinders not firing. Cause, the clips supplying power to the coil packs (3) of them were not seated properly from the last owner I would presume. It seemed as if the clips were touching in the boot but not "clipped".

Thanks all!
 
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