Idle problem, need help finding the cause.

[r-a-m-o-n]

Ok so i own this bike for 6 months now and already toured in july and august and it performed great.

Recently i found that after riding more than half and hour i.e. when the bike is fully warmed, there are times that when i stop the idle rpm drop too much: from 1250 to 900 more or less. Sometimes it happens when i stop at a red light or if i turn off the bike and turn it on when still warm for some seconds it fails to idle at the apropiate rpms.

If i apply some slight throttle the bike returns to normal idling without problem. If i let it idling low it stays at 800-900rpm for lets say 10 seconds and then you can hear like the bike accelerates the idle back to normal.

So far i did the following to try to solve the problem in this order: 1- synched throttle bodies bike runs smoother but idle problem continues, 2- changed all spark plugs (the ones i took out were fine but really old), 3-checked the air filter it was ok. I also did the TPS test and its well within specs.

So i dont know were else to look. The bike runs fine at all speeds and rpms the problem is only sometimes at idling when fully warm. It never happens when the bike is cold.

Any thoughts and ideas are welcome.

 

[TownsendsFJR1300]

Ok so i own this bike for 6 months now and already toured in july and august and it performed great.

Recently i found that after riding more than half and hour i.e. when the bike is fully warmed, there are times that when i stop the idle rpm drop too much: from 1250 to 900 more or less. Sometimes it happens when i stop at a red light or if i turn off the bike and turn it on when still warm for some seconds it fails to idle at the apropiate rpms.

If i apply some slight throttle the bike returns to normal idling without problem. If i let it idling low it stays at 800-900rpm for lets say 10 seconds and then you can hear like the bike accelerates the idle back to normal.

So far i did the following to try to solve the problem in this order: 1- synched throttle bodies bike runs smoother but idle problem continues, 2- changed all spark plugs (the ones i took out were fine but really old), 3-checked the air filter it was ok. I also did the TPS test and its well within specs.

So i dont know were else to look. The bike runs fine at all speeds and rpms the problem is only sometimes at idling when fully warm. It never happens when the bike is cold.

Any thoughts and ideas are welcome.

When you checked the TPS, did you check to make sure all the numbers inbetween the highest and lowest were ALL THERE and didn't skip or miss any. Very slow opening and closing of the throttle will show this. If it seems ok when cold, try checking the TPS as well when its hot (and the bikes acting up)....

Scott

 

[r-a-m-o-n]

I did check that all numbers in between were present. By checking the tps when warm do you mean shutting of the bike when warm and perform the test or is there a way to perform the test with the bike idling?

 

[Kriswithak]

Shouldn't be an issue you'll see between the bike being hot and cold on the TPS since its a sensor in the grip on the handlebars.
Do you have any aftermarket mods? Maybe an exhaust? Maybe reset the computer and see if that helps.

Might be an idea to flush your tank out and check the filter just incase any gunk has gotten in there and is affecting the flow of fuel, if it happens more often when your getting low on fuel that might be the issue.
Maybe put through some of the fuel additive cleaner you can buy at autoshops.

Also check what brands of fuel are recommended for use in bikes where you are, I know here Shell has a remarkably bad reputation and every dealer I have talked too has told me to catagorically not use it in a bike.
I've also had alot of people I know with bikes who have had idling and stalling problems stop buying Shell fuel and suddenly find their problems go away.

 

[r-a-m-o-n]

Ill check the fuel filter. Interesting what you say about shell because here has a high reputation and is the most expensive fuel of all the mayor brands to be found here. Will try switching fuel brands too.

The bike is fully stock except for the dual headlight mod and it had a lojack tracking system that i have removed by the company when i bought the bike. The problem started after a couple of months after i bought it so i think the mods arent affecting it.

 

[RJ2112]

..........

So i dont know were else to look. The bike runs fine at all speeds and rpms the problem is only sometimes at idling when fully warm. It never happens when the bike is cold.

Any thoughts and ideas are welcome.

This sounds like a vacuum leak to me, that only shows up when the parts heat up and expand. This would also be the case for an electrical connection the is making poor contact when the area heats up.

I would first inspect and tighten every connection between the head and the air box. All of the small rubber vacuum lines should be checked to make sure they are connected, and making a good seal. The intake runners should be checked.

While you are poking around in the area, I would inspect all of the electrical connectors to ensure the wiring is seated properly, and is free of corrosion.

 

[TownsendsFJR1300]

I did check that all numbers in between were present. By checking the tps when warm do you mean shutting of the bike when warm and perform the test or is there a way to perform the test with the bike idling?

When the bike starts acting up hot, turn it off and check it thru the diagnosis as if cold... The TPS is itself on the right side of the throttle body assembly, it has nothing to do with the hand grips, it senses the throttle position for the computer...

I agree, it can't hurt to empty the tank and clean it out as well as check the screen inside. Chevron "Techtron" works very well at cleaning the fuel system as well....

 

[ant_mb]

Shouldn't be an issue you'll see between the bike being hot and cold on the TPS since its a sensor in the grip on the handlebars.

The Throttle Position Sensor(TPS) is not on the handlebars as stated above. RTFM!!!:BLAA:

 

[FZ1inNH]

Shouldn't be an issue you'll see between the bike being hot and cold on the TPS since its a sensor in the grip on the handlebars.

WHAT? Where did you get that info?

This is incorrect. The TPS is on the engine and located down by the intake velocity stacks.

To Ramon:

Given that your bike is a 2005, have you had the TPS recall work done on it? IF so, I'd go back to them and complain again as they did have a second recall on some of the first replaced units so it could very well be another dead TPS. If you've never had it done, then this is the time to do it.

You're exhibiting the issues caused by a malfunctioning TPS for sure.

 

[Kriswithak]

Sorry my mistake. Best of intentions no need to jump down my throat. Just have never heard of people specifically saying to test the TPS while the bike was hot as opposed to cold.
Learnt something new.

I only commented because I had the same issue with my first bike very similar to this because the owner before me always parked outside near the ocean and the tank ended up extremely rusted which ended up causing alot of grief very similar to what your describing before getting alot worse. Of course I couldn't tell because it wasn't easily visible even when looking into the tank, and I wasn't in the habit of picking the tank up to check the fuel lines/filter. Could also be water leaking into your tank if its not covered.
It has pretty much the exact same kind of signs as the FZ6 TPS problem.

 

[Kilbane83]

How many miles are on it?
Check your plugs?
Air Filter?

TPS is a likely culprit on the '05 it was factory recalled for replacement. Check your vin on the frame. If the tps was done, it "should" have a small punch indentation on/near it signifying the repair was done. Here is a link if you want to do it yourself: TPS Replacement

If it's above 18k miles you might want to see about doing a throttle body synch. There is a good writeup here: Throttle Body Synch

A vacuum leak is the next most likely culprit if the above all checks out good. I'd pull your airbox out and reseat it on the cylinder head. If it's still doing it, you could have a faulty/worn out air cut-off valve possibly.

Fuel filter is also a diffinate possibility, but I'd check the stuff that doesn't leak gas all over the place first :thumbup:

That's enough to keep ya busy for awhile. If it's still doing it after that let us know and we'll put the communal thinking cap back on.

 

[r-a-m-o-n]

Thanks for all the suggestions, as i already did all basic mainteinance (synching, sparks, air filter) i will continue by checking the fuel tank and re testing the tps when warm just in case, then with more complex things like checking all air hoses, resetting comp, etc.

Just to know are there any NOT recommended cleaning products for pouring into the tank that would potentially damage the inyectors or the fuel lines? Or are all of them more or less the same?.

Ill update in a couple of days.

 

[PB Hand]

If you have not had the TPS warranty work done on the your 2005, I would recommend taking it in and having it done, regardless of the issue you're having. One of the reported issues with the TPS was bikes stalling when slowing down, which can obviously cause some major issues if it's still in gear. And, who knows, this may just be the culpret to your existing issue as well.