Strange Idle Issue

[quixitoc]

I've been having some issues with my 2004 FZ6 idling. When I turn it on cold, it idles around 1600-1800 (I set it there, more on that in a bit). I ride it for a bit and the idle stays the same. However, after about 10-20 minutes of riding, it idles around 2500-3000 RPM. After riding for about an hour or so, the bike begins to idle so low that it's at risk of dying out, around 600 RPM. I've raised the idle to offset this, and now it would do the same thing, except at 1000 rpm where I can keep it alive. The thing is, I turn the key off, let it sit for a minute, then turn it back on and it idles back at 1600-1800 again normally, and the cycle repeats. I've checked TPS values using diag mode during every "phase" of this and it consistently shows 16 with throttle closed and 101 with it open, so I don't think its an issue with that. Any ideas? Ive ran a tank with injector cleaner a few times, and throttle bodies have not been synced recently.

 

[Gary in NJ]

Have you seen this thread?

Faulty IACV

Good day! What are the symptoms of a faulty IACV 2005 FZ6N My bike idles at 1600-1700rpm coldstart Then idles 1200-1300 when warm But when i reached 3-4 bars of temp gauge My idle jumps around 1300-1600 rpm and runs a bit hot sometimes rpm hangs around 2k rpm Ive checked for vacuum leak, by...

www.600riders.com

 

[quixitoc]

Have you seen this thread?

Faulty IACV

Good day! What are the symptoms of a faulty IACV 2005 FZ6N My bike idles at 1600-1700rpm coldstart Then idles 1200-1300 when warm But when i reached 3-4 bars of temp gauge My idle jumps around 1300-1600 rpm and runs a bit hot sometimes rpm hangs around 2k rpm Ive checked for vacuum leak, by...

www.600riders.com

Yeah, just looked at that, I'll try to check out that system sometime and sync up the TBs. However, it doesn't address the really low idle after an hour. I'm thinking it could be something with fueling, though, because turning the key off and then on (priming the fuel pump) the idle returns to acceptable levels

 

[Gary in NJ]

Another known problem with the FZ6 that can cause all sorts of problems is a clogged screen on the fuel pump. It might be well worth your time to inspect the fuel pump assembly before going down the “ throwing parts at it” rabbit hole.

 

[trepetti]

Yeah, just looked at that, I'll try to check out that system sometime and sync up the

Have you seen this thread?

Faulty IACV

Good day! What are the symptoms of a faulty IACV 2005 FZ6N My bike idles at 1600-1700rpm coldstart Then idles 1200-1300 when warm But when i reached 3-4 bars of temp gauge My idle jumps around 1300-1600 rpm and runs a bit hot sometimes rpm hangs around 2k rpm Ive checked for vacuum leak, by...

www.600riders.com

Does anyone remember an old thread where someone tore down the IACV? I thought it was @FinalImpact (whatever happened to him?) but I did some searching and came up empty. I am interested in seeing the inside of it, as long as it's someone else's

 

[TownsendsFJR1300]

It wasn't Final impact and was 2-3 years ago.. I don't remember who it was but (I think mentioned/believe), coolant goes thru there. Cold coolant lets the ECU know and raise the idle till warm.

A through cleaning wouldn't hurt.

Checking the rest of the system, as noted, fuel pump, fuel filter, fuel pressure, etc should be done before throwing parts at it..

 

[BrunoPONCET]

J'ai eu quelques problèmes avec mon FZ6 2004 au ralenti. Lorsque je l'allume à froid, il tourne au ralenti autour de 1600-1800 (je l'ai mis là, plus à ce sujet dans un instant). Je roule un peu et le ralenti reste le même. Cependant, après environ 10 à 20 minutes de conduite, il tourne au ralenti autour de 2 500 à 3 000 tr/min. Après avoir roulé pendant environ une heure environ, le vélo commence à tourner au ralenti si bas qu'il risque de s'éteindre, autour de 600 tr/min. J'ai augmenté le ralenti pour compenser cela, et maintenant cela ferait la même chose, sauf à 1000 tr/min où je peux le maintenir en vie. Le truc, c'est que j'éteins la clé, la laisse reposer pendant une minute, puis la rallume et elle revient au ralenti à 1600-1800 normalement, et le cycle se répète. J'ai vérifié les valeurs TPS en utilisant le mode diag pendant chaque "phase" de cela et cela montre systématiquement 16 avec l'accélérateur fermé et 101 avec l'ouverture, donc je ne Je ne pense pas que ce soit un problème avec ça. Des idées? J'ai fait fonctionner un réservoir avec un nettoyant pour injecteur à quelques reprises, et les corps de papillon n'ont pas été synchronisés récemment.

 

[BrunoPONCET]

Bonjour
J'ai eu le même problème et en changeant le Boitier TPS (Throttle Position Sensor), ça fonctionne correctement maintenant

 

[Cocoloco]

It wasn't Final impact and was 2-3 years ago.. I don't remember who it was but (I think mentioned/believe), coolant goes thru there. Cold coolant lets the ECU know and raise the idle till warm.

A through cleaning wouldn't hurt.

Checking the rest of the system, as noted, fuel pump, fuel filter, fuel pressure, etc should be done before throwing parts at it..

I dont know if that was me, but i opened the iacv
Its the same how thermostat valve works cold coolant iacv retracts/open the air way, hot coolant closes it, ecu doesnt have control over this.

Have you seen this thread?

Faulty IACV

Good day! What are the symptoms of a faulty IACV 2005 FZ6N My bike idles at 1600-1700rpm coldstart Then idles 1200-1300 when warm But when i reached 3-4 bars of temp gauge My idle jumps around 1300-1600 rpm and runs a bit hot sometimes rpm hangs around 2k rpm Ive checked for vacuum leak, by...

www.600riders.com

Turns out my TPS is the issue afterall
Reads fine and no skips on diag mode
False reading when engine starts and vibrates, also heat soaking of tps may cause it to be faulty sending false signal to the ecu

 

[Piggy]

I dont know if that was me, but i opened the iacv
Its the same how thermostat valve works cold coolant iacv retracts/open the air way, hot coolant closes it, ecu doesnt have control over this.

Turns out my TPS is the issue afterall
Reads fine and no skips on diag mode
False reading when engine starts and vibrates, also heat soaking of tps may cause it to be faulty sending false signal to the ecu

Hey pal!
I wondered how you read the TPS when it was running and riding?

 

[Cocoloco]

Hey pal!
I wondered how you read the TPS when it was running and riding?

Multimeter

 

[Motogiro]

I dont know if that was me, but i opened the iacv
Its the same how thermostat valve works cold coolant iacv retracts/open the air way, hot coolant closes it, ecu doesnt have control over this.

Turns out my TPS is the issue afterall
Reads fine and no skips on diag mode
False reading when engine starts and vibrates, also heat soaking of tps may cause it to be faulty sending false signal to the ecu

This is something I've discussed a few times regarding a TPS showing good on diagnostic mode and passing resistance test with a multimeter. The TPS can generate noise. You may not see it with a digital meter but if you Looked at it with an oscilloscope you would see the noise. The ECU does not understand the noise and gives it's best guess per the anomaly. You might even be better off using an analogue meter instead of the multimeter because of the sample rate.
They also sell some cheap self contained O'scopes these days.

 

[Piggy]

Multimeter

I gotta ask how you got into the tps wiring and then held a multimeter while riding?!

 

[Gary in NJ]

Back-pin the connector and tape the meter to the tank.