How to Change my Throttle Position Sensor (TPS)

[beuwiq]

Glad you got it operating again! Just a little bit of waiting and messing around!
Here's to keeping dirt in plants and out of the tank! :thumbup:

lol Blah

Thanks once again

 

[beuwiq]

A quick recap for future reference. A lack of fuel pressure/fuel volume would hinder the engines ability to accelerate as the enrichment part of the fuel map is begging for more fuel, but the pressure and volume drop so it cant meet the demand and the engine misfires.





JJD952 Fuel Pump causes misfire

Nice recap really nice :thumbup:

 

[mgdaubo]

Hi,

My bike is 2005 FZ6N, it has some symptoms that makes me think about changing TPS:
- Rough idle, cold start it usually idle at 1500, then when warmed up it drop to 1100 - 1300 rpm.
- Hesitate rev up, poor throttle response. If I let off and then rev up the throttle, it takes some delay before rpm goes up. I feel like the throttle system or the chain has too much slack.
- RPM is not stable while trying to maintain constant speed, it is going up and down, oscillating like I am trying to manipulate the throttle.
- Vibration on the whole rpm range. It is worse at high rpm, in fact I am not confident to run more than 7000 rpm.
- Sometime back firing (very rarely).

I decided to change TPS. Today after disassembly all and take out the old TPS, I realize this old TPS has the shaft rotating clockwise while the new one I ordered has counter-clockwise shaft I never think there are 2 types of TPS which have identical look but 2 different shaft rotating direction??? What is yours? what is the original part number?

Apart from TPS, what else do you suggest to check? I am thinking about throttle body sync, injector and pump clean, plug and cap check. What do you think?

Thank you.

 

[mgdaubo]

I am still waiting for the "clockwise TPS" to come. I will update the result after changing it.

Here is another symptom I noticed recent days:
- After riding for around 10-15 minutes, if I pull the clutch and release throttle it will idle at 1300 rpm, then I slightly increase the throttle, now rpm will decrease to around 1000 instead of increasing. Then I give more throttle, rpm will jump directly to 3500, it is almost no way to keep rpm at 2000 to 3000. (Note that I am pulling the clutch).
- Then I switch off and switch on the key, it is then back to normal. Then it will happen again after 10-15 minutes riding.
- But still maintaining constant speed is very difficult all the time, rpm is jumping back and forth, feel like it is oscillating and kick the tire, you can here the engine and exhaust sound change like a wave.

Does it indicate TPS problem? Why does it disappear when switch off and on the key, then back after 10 minutes?

 

[TownsendsFJR1300]

I am still waiting for the "clockwise TPS" to come. I will update the result after changing it.

Here is another symptom I noticed recent days:
- After riding for around 10-15 minutes, if I pull the clutch and release throttle it will idle at 1300 rpm, then I slightly increase the throttle, now rpm will decrease to around 1000 instead of increasing. Then I give more throttle, rpm will jump directly to 3500, it is almost no way to keep rpm at 2000 to 3000. (Note that I am pulling the clutch).
- Then I switch off and switch on the key, it is then back to normal. Then it will happen again after 10-15 minutes riding.
- But still maintaining constant speed is very difficult all the time, rpm is jumping back and forth, feel like it is oscillating and kick the tire, you can here the engine and exhaust sound change like a wave.

Does it indicate TPS problem? Why does it disappear when switch off and on the key, then back after 10 minutes?

Curious, did they send you the wrong part? I assume it's OEM, not a Chinese knock off your installing?

The TPS can be checked by going thru the dash and slowly moving the throttle (open and closed) watching the #'s.
There shouldn't be any skipping, all linear.

The TPS can do some weird things when acting up (even if it passed the above test). Turning the power on and off and getting it to run
normal, to me, does not sound like a fuel issue. That issue wouldn't change by turning off the engine and re-starting,

Get the new TPS installed, one step at a time...

I gather you've already tested the battery (Load test) and the tightness of the battery lugs..

 

[mgdaubo]

Thanks for your response, TownsendsFJR1300.

Yes that TPS I got from China supplier, although they said it is Japan genuine new TPS, part number is 5FL-85885-01-00 or 5FL-85885-02-00. Now they are sending me another one with clockwise rotating direction, let's see how it works, I am still waiting maybe for 1 more week.

Unfortunately I got the bike without stock instrument clock, it came with Koso RX2 clock, so I cannot do the TPS test. I just try measure it by ohm meter and set it to 0.63 ~ 0.73V at no throttle as said in manual.

For the battery: I did check the connection, the rectifier, and the stator, seem no problem. Battery voltage is 12.7V when off, 12.5V when key on engine off, at idle it slowly increases to 14V, and 14V at 5000 rpm. Is this normal?
How to do the load test? and if it fails then battery will need to be changed?

I too don't think it is injection dusty. I am planning to do step by step: TPS change, throttle body sync, then injector clean. I will update result of each step.

 

[TownsendsFJR1300]

Your voltages and charging system are all fine...

Load test is done with a machine (auto parts store, etc) for free (here in US at least).

A poor man's way of load testing is simply watch your volt meter as you CRANK OVER the ENGINE. If the voltage drops
to approx 11 volts, it's on it's last legs...

I doubt your issue is the battery.

There was a re-call on the TPS's (at least in the states) that year. If you have a Yamaha shop nearby,
they can look up your VIN #.

If it's NOT been changed, they'll change it out for FREE, No labor, no part charge, etc. And it's genuine OEM..

 

[mgdaubo]

Thanks TownsendFJR1300.

I will leave the battery at last because its voltage seems to be ok and it is relatively new (1 year old).

Since last 2 weeks the symptom is more clear pointing to the TPS: bike jerking at constant throttle or during deacceleration, and when engine is hot the idle rpm drops and some time stall, lose power. Is this TPS problem?
It is not easy to contact Yamaha in my country, I will have to deal with it by myself.

The TPS part finally arrived today after 3 weeks of delivery, I will give it a try maybe tomorrow.

Now I have question regarding to how to correct assemble the TPS:
- My bike doesn't have stock clock, it is Koso RX2 clock with the previous owner, so I cannot do TPS adjustment by looking at the diagnostic number on clock. I can only measure the output voltage of the TPS. The manual says it is 0.63V to 0.73V with closed throttle, I can do this adjustment during fitting the TPS, but I am thinking because the Idling screw is also affecting the initial angle of the throttle shaft (can anyone confirm?) then adjusting the TPS to have 0.63V~0.73V is not enough to ensure the right alignment of the TPS with regarding to the throttle shaft angle? Is my concern valid or I have wrong understanding?
- If my understanding is correct then I will need the voltage of the TPS when throttle is fully open. Manual says nothing about this. Did anyone try measuring once? Maybe I will have to play with both adjusting the TPS and the idle screw to get correct voltage at fully close and fully open throttle?

 

[TownsendsFJR1300]

I'd turn the idle screw down approx half ways for now. You may have to re-adjust once the TPS is in and it's idling.


.

 

[mgdaubo]

I'd turn the idle screw down approx half ways for now. You may have to re-adjust once the TPS is in and it's idling.

I got it, thank you.

From other photos of throttle bodies on this forum, I see the idle adjusting screw has no mechanical link to the throttle shaft, I think it is just tuning the air flow (going through another path, not through throttle butterfly valve) for idling, will not affect the angle of the throttle shaft at idle. So I will go ahead to change and adjust the TPS as said in manual, I will let you know the result.

Thank you.

 

[mgdaubo]

I changed the TPS, adjust it to 0.68V at fully closed throttle and after 3 day riding I can confirm that all the symptoms I mentioned earlier have gone. The bike run smoother, no jerking, no rpm drop and power lost when hot... And I also notice the bike run a little bit cooler, around 5 degree C cooler than before, not pretty much sure but the coolant temperature gauge is saying that.

Thank you Scott for your help.

 

[TownsendsFJR1300]

Excellent and your welcome. Glad you got it straightened out.

Ride safe!!

 

[TKBone]

Thank you so much, I adjusted my TPS from 13 to 17. It's much more relaxing to ride now, smoother to shift! Couldn't have made it without you!

 

[TownsendsFJR1300]

Just an FYI, adjusting the TPS so the lower # is HIGHER, the computer thinks the throttle is OPEN more (which it isn't).

Thus adding a little more fuel to the mix (for the same RPM's).

The early FJRs were notoriously lean up to 3K RPM's, surging etc...

 

[TKBone]

I cutted the snorkle,

so a bit more fuel is desired also, even if the Mod is small.

Test rode it on a nearby mountain road, it's so more relaxing to shift. My overall speed seems to have altered. Plus there is a great part for WOT, dude i never reached the limiter in third before! Beeing new to the world of screws and stuff this was some major surgery to me :cheer: so your how-to made me some happy fella!

 

[Zampix]

I would like to share a useful video:

https://youtu.be/qMaoqeEukEQ

Inviato dal mio VFD 610 utilizzando Tapatalk

 

[TKBone]

Mi scusa ma non funziona! Warner claimed the rights of the soundtrack, é possibile to upload without music?
Grazie mille!