Bike has rough idle, dies

[Abyss]

So I'm going through the service manual now to try and troubleshoot a rough idle. Basically what happened is that a couple days ago, I noticed the bike would die sometimes on idle. Yesterday I took the bike literally 50 feet and held in the clutch and it died. Tried to start it and it wouldn't do anything without some throttle, and even then letting the RPMs drop made it stall.

Now every time I start it, it starts idling high (~1600 RPM) even though it had previously been idling at 1300 just fine. The idle then gets progressively lower and after about 5 minutes it chugs and dies.

The throttle stop screw has absolutely no effect for whatever reason. Turned it 100% both ways.

It's a 2006 CBR600RR, 15.5k miles, with a full system Yosh and PCIII. It's possible the PC may have been disconnected from the battery. I strengthened the connection but it has had no effect.

It runs just fine on the throttle though, no difference in acceleration.

I'm thinking this may have to do with the fuel maps, but does that even make sense? I don't know how else it could have gone 4,000 miles fully functional and then suddenly decide to crap out. Dirty injectors? Failing fuel pump/dirty filter? What do you guys think?

EDIT: Just disconnected the battery and reset the bike for good measure, no effect.

 

[ALANRIDER7]

Remove the PCIII completely and see if the idle changes.

 

[Abyss]

Remove the PCIII completely and see if the idle changes.

Good idea. I'll work on that.

 

[EastBayDave]

as Alanrider7 says, you might need to re-flash the pciii ?

I'd also throw a bottle of injector cleaner in the tank if the above don't work.

Have you tried turning up the idle adjustment?

 

[motopsyco59]

Valve lash?

Cheers!

 

[Ol' Gravy Leg]

Sounds like the ECU is turning on the fast idle. That is why the set screw has no effect and is now out of adjustment.

Your ECU could be getting faulty signals from one or more sensors (engine coolant temp., etc.).

Is the bike throwing any fault codes?

 

[Abyss]

as Alanrider7 says, you might need to re-flash the pciii ?

I'd also throw a bottle of injector cleaner in the tank if the above don't work.

Have you tried turning up the idle adjustment?

I turned it all the way both ways. It did absolutely nothing, which makes me think this is a fuel maps issue...

Sounds like the ECU is turning on the fast idle. That is why the set screw has no effect and is now out of adjustment.

Your ECU could be getting faulty signals from one or more sensors (engine coolant temp., etc.).

Is the bike throwing any fault codes?

I don't know how to check for fault codes. I'm thinking this is an issue with the Power Commander overriding the ECU for idle throttle position. Just a small turn will keep it running smoothly but as soon as I let off it dies.

 

[Ol' Gravy Leg]

I turned it all the way both ways.

Oh, boy. It is definitely off now--which will cause it to die as soon as the fast idle turns off (after the bike thinks it is warmed up). If your bike gets a bad signal, it will turn the fast idle on and off. Hence, going from 1600rpm to dying.

I don't know how to check for fault codes. I'm thinking this is an issue with the Power Commander overriding the ECU for idle throttle position. Just a small turn will keep it running smoothly but as soon as I let off it dies.

I can't remember if it a jumper to tell you fault code. (been a while since I owned a CBR). But, the bike will squawk at you with FI and flashing. You count the flashes to determine the code.

[youtube]BZ4KJsyqs1g[/youtube]

I doubt it is the PC. But, that is indeed your first step: disconnect it.

 

[Abyss]

Oh, boy. It is definitely off now--which will cause it to die as soon as the fast idle turns off (after the bike thinks it is warmed up). If your bike gets a bad signal, it will turn the fast idle on and off. Hence, going from 1600rpm to dying.

Well I turned it back to the middle

I can't remember if it a jumper to tell you fault code. (been a while since I owned a CBR). But, the bike will squawk at you with FI and flashing. You count the flashes to determine the code.

[youtube]BZ4KJsyqs1g[/youtube]

I doubt it is the PC. But, that is indeed your first step: disconnect it.

It's not giving me any issues like that and the FI light stays off. All systems read nominal, right up until it dies.

 

[Ol' Gravy Leg]

Bypass the PC.

Check connectors to the ECT and MAT (temp at your air box). The ECU uses these to determine when to turn on the fast idle. Also, watch the gauge temp to see if it is lewy.

Once you fix and adjust the fast idle, then you can correct the set screw.

 

[Abyss]

Bypass the PC.

Check connectors to the ECT and MAT (temp at your air box). The ECU uses these to determine when to turn on the fast idle. Also, watch the gauge temp to see if it is lewy.

Once you fix and adjust the fast idle, then you can correct the set screw.

It uses fast idle until it reaches 100 degrees, and that's when it starts to rough idle. Does that mean anything in particular?

 

[Abyss]

UPDATE: Power commander won't even synch with my computer. Basic shit is not working. Frustration.

I'm pretty sure this is the PC being lame. It got disconnected from the battery and I have read on several forums that can cause it to act really screwy. Problem is, if I can't get it to connect, I can't reset it.

 

[SD Hornet]

Is the battery and charging system giving you at least 13.3 volts at regular idle?

 

[Abyss]

Is the battery and charging system giving you at least 13.3 volts at regular idle?

Averages about 13.3 volts. Nothing amiss there. If I could just connect to my fucking Power Commander I could probably figure this shit out. Does anyone know if there's a manual reset I can do, like holding the buttons or something?

 

[ALANRIDER7]

UPDATE: Power commander won't even synch with my computer. Basic shit is not working. Frustration.

I'm pretty sure this is the PC being lame. It got disconnected from the battery and I have read on several forums that can cause it to act really screwy. Problem is, if I can't get it to connect, I can't reset it.

Disconnecting a properly working PCIII shouldn't cause any problems.

Make sure you have a good 9 volt battery plugged into the PCIII, then connect it to the computer and make sure it connects. You should be able to read what map is on it. If you have the right software and a good connection, it should work. If it won't boot up, it's bad.

 

[Abyss]

Disconnecting a properly working PCIII shouldn't cause any problems.

Make sure you have a good 9 volt battery plugged into the PCIII, then connect it to the computer and make sure it connects. You should be able to read what map is on it. If you have the right software and a good connection, it should work. If it won't boot up, it's bad.

Realized I didn't plug the USB into the PC III all the way Read on the FAQ that it has to snap into place and I have a phobia of forcing plugs into slots and breaking them. Just had to force it a little. I'll see what maps it sends back and try reverting to stock if there's nothing screwed up.

PC III is powered by the bike so it is getting enough juice. The fuel readout on the side is operational.

 

[Abyss]

Just checked PC III, the bike chugs on both stock and aftermarket maps.

Throttle stop screw continues to do absolutely nothing.

How would I know if the bike isn't firing on all cylinders or has really dirty injectors?

 

[Ol' Gravy Leg]

Just checked PC III, the bike chugs on both stock and aftermarket maps.

Throttle stop screw continues to do absolutely nothing.

How would I know if the bike isn't firing on all cylinders or has really dirty injectors?

Pull the plug wires one by one. (You'll get a tiny shock if the bike is running.)

What is stopping you from bypassing the PC? It is seriously 4 plugs to unplug and plug back in.

BTW, a bad PC ground will make your idle funny too.

 

[angelsndevils]

+1 for tight valves. Runs somewhat decent until everything gets hot and expands then gets too tight and dies unless you give it more fuel to keep it going. When's the last time the valves were done?

 

[Abyss]

I'm uploading a short video right now to give you guys an idea of what's going on.

+1 for tight valves. Runs somewhat event until everything gets hot and expands then gets to tight and dies unless you give it more fuel to keep it going. When's the last time the valves were done?

Says in the manual it needs to be serviced at 16k... I'm at 15.7k as it is. Maybe that's it.

Pull the plug wires one by one. (You'll get a tiny shock if the bike is running.)

What is stopping you from bypassing the PC? It is seriously 4 plugs to unplug and plug back in.

BTW, a bad PC ground will make your idle funny too.

It's all fucking goober engineered and there are tie wraps everywhere and I'm not touching that shit unless I can figure out how the hell I am supposed to put it back.