Throttle position sensor

[agricola]

Sweated away in the garage to get this little foccer off yesterday/today. The bikes not been accelerating smoothly from closed recently, so I took a stab at the TPS as the most likely culprit, given the evidence. Manual says 4k-6k oms closed and 0 to 3.5k-6.5k ohms. Mine reads 0.34k ohms closed and 0.34k-1.6k ohms when wound on, and Ive cross checked with another meter too. Theres a lot of stuff to get off to get at the little bugger too, just for the sake of two screws. Would have been much quicker to just drill two holes in the frame in line with the screws


Price from F--l--s, £223.63


Prices on ebay range from £18 upwards. I think i'll settle for a slightly more expensive one and avoid the unpackaged available from people who can't spell the text in the adverts correctly.

[Grahamm]

Did you check the TPS range using the Diag mode on the instruments?

[agricola]

Did you check the TPS range using the Diag mode on the instruments?

No, I used a multimeter neither mention using the diagnostics mode. Given the findings, surely that points to the TPS? Unless you can tell me otherwise?

[unfazed]

Use the diagnostic mode first and if it cannot be set to the correct number then test it with a meter. It is easier to test the FI model TPS than the Carb bikes as you can check the full range of the TPs

[Grahamm]

No, I used a multimeter neither mention using the diagnostics mode. Given the findings, surely that points to the TPS? Unless you can tell me otherwise?

Try this:

With the ignition off and the kill switch on, lift the tank and disconnect the fuel pump connector.

Hold down Select and Reset and switch on, keeping the buttons pressed for about 8 seconds until all the displays disappear except for the clock and trip meter.

Press Select until you see Diag appear on the display, the press Select and Reset again for 3 seconds.

Turn the Kill Switch off and you should see Diag 01 on the display and a number.

Open and close the throttle and the numbers should scroll smoothly from between 15-17 and 97-100 which are the readings from the TPS.

If you don't get that, or it skips around, the TPS is probably faulty.

[agricola]

Comments are appreciated, but Id already got the TPS off, relying on the info from the multi meter. The new TPS will be here tomorrow, first thing is to check the readings of the new one to see if they conform to the info in the manuals. If they do, then Ill fit it and refit assemblies.

[unfazed]

Missed that you were referring to the FZ6 and changed my post to reflect same and the test is very accurately mentioned by Grahamm

[agricola]

Installed the new TPS this afternoon. Two bits of good news, no parts left over, and the bike is running much better now, thottle response is as it should be. I checked the resistances of the new one before fitting and before refitting the throttle bodies, just to make sure it was within spec. Graham, is the info you posted regarding diagnostics, what do the numbers refer to, and are they adjustable through the system? Where did you find that info?

[Grahamm]

I checked the resistances of the new one before fitting and before refitting the throttle bodies, just to make sure it was within spec. Graham, is the info you posted regarding diagnostics, what do the numbers refer to, and are they adjustable through the system? Where did you find that info?

The info came from the Haynes manual, but it's the same in the official Yamaha Service manual.

The values are for resistance (I think), but what really matters is that they scroll smoothly up and down through the range, from what I recally, the original TPS had an issue where it could suddenly drop to zero causing the engine to die unexpectedly.