started but woulbn't throttle up

[Burns1]

I was out today on a ride and after about 100 miles we stopped to top up the tanks and warm up a bit. I went to leave the pump and the bike would start fine but as soon as I gave it any gas it would die. We pushed it off to the side and took a smoke and restroom break... about 10-15 minutes. Tried to leave and it did the same thing for about the first three tries and then suddenly it would take throttle input. Another 75 miles later we stopped for lunch and had no issues with it. This is a 2008 with about 27k on the clock. This is a used bike so I have no idea what maintainence has been done to it but I do know the recalls were done. The bike is running fine although there is a bit of a surge to the idle. Does anyone have any idea what could have caused this? Weather was cool (45°) and the temp gauge was right in the normal range. This is the first time I've ever had this happen. Thank in advance!

Burns1

 

[Twigg]

Back in the day I would have said it sounds like it was flooding, or the pilot jets were blocked giving no gas at part throttle.

With the new-fangled trickery I'm a bit stuck for a suggestion, other than maybe the fuel pump failing intermittently and not pressurising the rail.

 

[bluesdog]

Check the easy stuff first, such as battery terminals for clean and tight connections

 

[Hemicuda]

Could it be gas tank cap vent issue..... causing vac in tank....fuel pressure problem???

 

[Geezer]

Since it happened right after you gassed up I would suspect the fuel. A little water or other stuff could have been introduced and hopefully you have now flushed it through. It can't hurt to look into the tank with a light and see if you can see anything besides pure fuel.

 

[rPGoatBoy]

Is it a California bike?

 

[Big Sky]

What is the idle speed? I've read that these are sensitive to proper idle speed - 1,100-1,200 RPM is minimum. I believe a symptom of too low idle is a tendency to die when the throttle is opened.

 

[Burns1]

I don't think the battery terminals were the issue. It turned over fine, started fine, just wouldn't take any throttle input at all.

Fuel Pressure...no idea but other than this one little glitch, the bike ran great all day long. And I would have no idea how to check fuel pressure. (really need to pull the trigger on a service manual)

No..bad gas is exactly what the guy I was riding with said. He had run into the same sort of issue with his 'Wing in the past. exact same symptoms. So I'm thinking that may be the problem. I'll probably throw a little Stabil into the tank just as a precaution.

California Bike? No idea. How can I tell?

And lastly, idle speed is right between 1000-1200. I might have to bump that up just a little.

I'm planning on going to Spearfish in June so I'll be keeping a close eye on this issue. I'm really hoping I never see it again, and I sure as hell don't want it to pop up on that trip. Thanks guys for the ideas.

Burns1

 

[Big Sky]

You said: "The bike is running fine although there is a bit of a surge to the idle." Now you indicate warm idle is between 1,000-1,200 RPM. That's a lot of "surge." I've had three FJRs and the idle for all three was very steady. A TB sync sounds like it is warranted.

 

[Burns1]

Yea, I was thinking I might have to do a TB sync. Anyone in the Denver area got a Sync tool and want to help me do a sync? lol I hate the thought of spending $100 on a tool I might not use very often. Yep, I'm cheap!

Burns1

 

[rPGoatBoy]

California Bike? No idea. How can I tell?

Not sure there's a way to tell by the VIN, and I don't know where the model # can be found on the bike, however if you have two hoses sticking out at the bottom of where your front fairings come together, then you have a California bike. The second hose is from the charcoal canister that Cali bikes are required to have.

Check out this thread. I had this issue and deCalifornized my bike because of it. Fixed the problem instantly.

 

[wmadoty]

Check the air filter while you are in there. If it is "really" plugged up (or damp) it would idle great but stumble under load. Maybe run great coming down the hill but have trouble going up. Just something to look at.

 

[stealth1]

Put a new battery in it and it will fix it. Several gen2's have had this problem. Extra draw when starting in cool conditions drops battery voltage and "confuses" the ecu. Seems like this is most common on 07-08 models. Takes most of us a while to figure it out because battery seems fine otherwise.

Save yourself a headache and buy a battery.

check this

https://www.fjrforum.com/forum//index.php/topic/162349-gen-ii-strange-cold-start-issue/

and this

https://www.fjrforum.com/forum//index.php/topic/160484-2008-ecu-swap-question/

 

[HotRodZilla]

Did you fill it up, and then put it on the side stand while you took your break? IF you have a California bike, a bunch of fuel probably vented into that canister and had to vapor out before you'd get any power.

If you do that with a non-Cali bike and there is any heat, you'll come back to a small puddle of fuel under your bike. The California bikes vent into that charcoal canister and FUBAR the fueling.

 

[Burns1]

Well, we will see if a new battery fixes the issue. I was hesitant to replace the battery for this, but since I went ahead and accidentally drained the battery I figured it was a good time for a new one. Of course I may never see the problem again and I'll never know what actually fixed it. Thanks everyone for your suggestions.

Burns1

 

[ionbeam]

The odds of the problem being the battery approaches zero, unless it's loose wires.

Check the diagnostic code history.

The fact that it has happened once(?) may have just been a fluke combination of things that will never be repeated again.

Failure to accept throttle can be a vacuum leak (but usually comes with a high, floating idle); low output from coils (usually heat related and will have issues running when the coils get wet, could be coil signal wire problem, do you have an aftermarket cruise control?); too rich (black exhaust smoke, gas smell, black plugs); too lean (fuel delivery, tank venting, bad gas, pinched hose, fuel pump wire issue); failing or maladjusted Throttle Position Sensor (will happen mostly when the engine is hot and hasn't sat long with the engine off); sensor wires pinched between engine covers and engine case (usually noticed after some service like valve adjustments, clutch work or stator cover removal).

I recommend starting with checking for engine codes. If there are no codes and this happened only once, then as hard as it may be, just ride the sucker and expect that the problem won't happen again.

 

[stealth1]

Battery has fixed this problem in 3 bikes I know of. All 07's or 08's.

 

[ionbeam]

...the bike would start fine but as soon as I gave it any gas it would die...Tried to leave and it did the same thing for about the first three tries and then suddenly it would take throttle input...

Battery has fixed this problem in 3 bikes I know of. All 07's or 08's.

Unless the running ignition voltage is <8.0 volts I sure would like to know how battery voltage keeps the engine from revving over idle speed. My Gen I with a smoked Electrosport stator managed to run just fine with the running battery voltage around 9.0 volts (as I nervously streaked toward home hoping to make it to my garage before flame-out).