The Yamaha Road Star Warrior Forum

I'm running Tim's map (I entered all the values on the zero map from the picture in http://rswarrior.com/forums/t/49108.aspx).

It's been happening since I've had the bike.  I just accellerate hard and the problem goes away.

I've gone through several maps.

I bought the bike with HK 3-in straights, then went to a Jardine slip-on, and now have the Baron's Sport Nasty (which is quieter so I'm more likely to accelerate hard since the cops won't hear me two blocks away).

Playing the Vegas odds this is a TPS problem.  I remember a few posts last two years where TPS recall was done and it wasn't done right (or the TPS was bad) so this remains the only common thread.

Also you might read the service manual to see how the TPS actually works then look at the 'workings' on your bike and see if there's crud or debris.

Hope this helps.

Had the recall done last year.  I'll get a cheap multimeter and do the check IAW the service manual.

UPDATE (2 AUG 08):

I got a multimeter and did the test.  I'm getting about 5.6 kOhms and the resistance does not change with the throttle.  I haven't removed the TPS yet.  I'll do that tomorrow and see if the TPS is somehow not coupled to the throttle bodies (my kid was distracting me).  Is this what was wrong with the sensors that were recalled?  Somehow, the bike runs fairly well and I can ignore the sputtering and I can even keep it from happening if I flog the throttle from every stop.  But it's not right.

Ordered the TPS.

Apparently it's a new part and has a different #: THROTTLE SENSOR ASSY 3P6-85885-00-00  (replaces 5PX-85885-00-00)

I'll be sure to check the resistance before installing.

PS: The "RSW6" coupon code still works.

SWODude:

Had the recall done last year.  I'll get a cheap multimeter and do the check IAW the service manual.

UPDATE (2 AUG 08):

I got a multimeter and did the test.  I'm getting about 5.6 kOhms and the resistance does not change with the throttle.  I haven't removed the TPS yet.  I'll do that tomorrow and see if the TPS is somehow not coupled to the throttle bodies (my kid was distracting me).  Is this what was wrong with the sensors that were recalled?  Somehow, the bike runs fairly well and I can ignore the sputtering and I can even keep it from happening if I flog the throttle from every stop.  But it's not right.

Be sure you are using the proper scale on your VOM for step 2 when checking the variable resistance while opening the throttle and that you're connected to the proper terminals of the TPS. The test is performed w/ the TPS 3-prong plug disconnected and starts at a much lower ohm reading. If you're on to high a scale (high resistance) you won't see a change.

It's possible that the TPS recall wasn't done properly by the technician. The factory manual is well documented for the procedure (some simple math based on the resistance of the new TPS) as i replaced mine out of pocket before the recalls ... Here's a thread of mine showing my tools of choice for testing & replacing:

Disclaimer: This contribution/reply of mine is in no way an endoresment of replacing your TPS. Just presenting the facts

AlanH:

Mon, Oct 2 2006 9:33 PM

http://rswarrior.com/forums/p/23954/356933.aspx#356933

Photos of TPS during testing & replacement as well as crimp terminals & tools used during R&R and calibration

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Checking & Adjusting Throttle Position Sensor Angle - Terminals (T) 2 & 3

[

Adjusting Throttle Position Sensor Angle (CLOSED) - T2 & T3 - Throttle Closed 667 ohm. This is a very sensitive adjustment and the reason for a tolerance/range. I shot for the mid-range - This adjustment is done on a lower resistance scale of the VOM!

[

Rechecking Maximum Throttle Position Sensor Resistance - T2 & T1

---

View of TPS coupler assembled. From L to R:  Blk = T2, Yel = T3, Blu = T1

[[

Thanks.  I did the test per the service manual, and I got 5.6 KOhms, which is fine for the maximum resistance.  But with the throttle closed, it should be between 650-750 Ohms.  My TPS is reading 5.6 KOhms with the throttle closed, open, in between.  It doesn't matter.  the engine runs fine for the most part, starts right up, only sputters occasionally between 1500 and 2000 rpm with about 10% throttle, often after an upshift (and yes, I roll off when upshifting).  It does run a bit rich at idle, no matter how my PCIII maps is set up.   

UPDATE:  AlanH, thanks for the pictures.  I just bought the torx set at the local NAPA, and quickly removed the TPS.  I went through the inspection procedure IAW the manual. 

I began with step 1 - testing the resistance between black and blue.  Got 5.62 kOhms.  Then I went to step 2 - checking blue and yellow.  The resistance varied between 120 Ohms and 5.36 kOhms.

So I went back to step 1 to see if the black-blue resistance should be changing.  Couldn't find the info.  So I went to step 3 - adjusting the angle of the TPS.  This step has a formula to tell you, based on your maximum black-blue resistance, where the closed-throttle values should be.  BINGO!!!!  I knew the black-blue values should change with the throttle postion.  They weren't changing.  So I am now 100% sure the TPS is the problem.  I should be getting my new TPS later in the week.

Would this problem have showed up in the Diagnostics (code 01, throttle angle)? Were you getting an engine light or trouble code??

If the old part is still in there... I shure would like to know what the readout looks like in the Diagnostics.

SWODude:

UPDATE:  AlanH, thanks for the pictures.  I just bought the torx set at the local NAPA, and quickly removed the TPS.  I went through the inspection procedure IAW the manual. 

I began with step 1 - testing the resistance between black and blue.  Got 5.62 kOhms.  Then I went to step 2 - checking blue and yellow.  The resistance varied between 120 Ohms and 5.36 kOhms.

So I went back to step 1 to see if the black-blue resistance should be changing.  Couldn't find the info.  So I went to step 3 - adjusting the angle of the TPS.  This step has a formula to tell you, based on your maximum black-blue resistance, where the closed-throttle values should be.  BINGO!!!!  I knew the black-blue values should change with the throttle postion.  They weren't changing.  So I am now 100% sure the TPS is the problem.  I should be getting my new TPS later in the week.

My original reply has several threads that i suggest you read as they are quite definitive regarding the TPS as well as using the diagnostic to check the throttle angle!

I seriously doubt that the bike would run in gear at all if the TPS wasn't outputting a variable voltage once there was an output from the speed sensor to the ECU as designed. Here is some reading mat'l: http://www.fileden.com/files/2008/1/1/1673654/Throttle%20position%20sensor%201-13.pdf

Blue, Black wires that connect to terminals 1 & 2 respectively represent the fixed leads of the potentiometer and do not vary in resistance

Yellow (wiper), Black wires that connect to terminals 3 & 2 respectively represent the wiper lead (variable) & fixed lead of the potentiometer and will increase in resistance as the TPS shaft is turned CW when facing the hex female shaft

Here's step 3, from page 7-64 of the manual:

Service Manual:

3. Adjust:

• throttle position sensor angle

a. Disconnect the throttle position sensor coupler

from the throttle position sensor.

b. Connect the pocket tester (Ω × 1k) to the

throttle position sensor.

Positive tester probe → blue 1

Negative tester probe → black 2

c. Measure the throttle position sensor maximum

resistance.

d. Calculate the throttle position sensor maximum

resistance when the throttle is closed.

Throttle position sensor maximum

resistance (throttle is fully closed) =

Maximum resistance × (0.13 ~ 0.15)

 So am I missing something here?  If black-black resistance should be constant, then why are they telling me in Step 3 that the resistance should be lower with the throttle closed?  And if my TPS were fine, then why do I get the sputter with abrupt throttle changes, especially when I hit bumps or potholes?  And no, I'm not getting any trouble codes or warning lights. 

When all else fails using an ohm meter to set the TPS give this meethod a try:

The throttle plates should be checked for balance. Remove whatever intake you have to gain access to the throttle bodies. Use two pieces of identical diameter wire to check, welding rod/wire works well. Open the throttle a bit & place the wires down inside the throttle bodies past the throttle plates,. Close the throttle. Now pull up on the wires. They should both have the same amount of drag to remove them. If they are not identical use the balance screw located between the throttle bodies to make an adjustment.

Warm up the bike & sync the throttle bodies.

Back off the idle speed adjuster until the adjustment screw is not touching the cam.

Your throttle plates should be in the fully closed position.

 Tip: when turning the idle adjustment screw add a bit of throttle with the twist grip to relieve pressure on the idle adjustment screw.

Loosen the TPS mounting bolts a bit.

Go into the diag mode 01 & set the TPS to 20 with the throttle closed.

Tighten the tps screws.

Adjust the idle screw so the bike will idle then reset the idle to 950 rpm after running for 20 minutes.

If you still have a flat spot at 1900/2000 you can:

Get another TPS.

Get the injectors serviced.

BTW: if your running unbaffled exhaust or large diameter exhaust pipes it will effect off idle/low rpm throttle response.  Try a tailpipe reducer available at most auto parts stores. Measure the inside daimeter of you pipes & get one that filts the inside diameter & has an outlet diameter in the 1 & 5/8  to  1 & 11/16 range. Install it/them with the small end to the rear & secure with a sheet metal screw from the wheel side or underside of the pipes.

Good morning!

Just an observation I learned recently (Thanks Darkstar!) is NOT to mess around with the throttle body sync screw(s) because without a meter on the throttle bodies while adjusting chances are you will just mess things up worse.

Here's what I would consider doing;

1. recalls (TPS and CPS)

2. the perfect install in the pc3

3. load your favorite map

4. set %throttle to zero at idle

5. hook up a manometer (or make your own DIY manometer) by way of the instruction on this website and synch your throttle bodies following your service guide.

At this point it's time for a test ride and see what the results are. Depending on whether its back firing or "coughing" through the throttle bodies and when it's doing it(up shifting, down shifting or whatever) you'll then start adjusting the pc3 for lean or rich conditions.

Not to be critical of your work but I might question that fuel line reroute job....could it be causing a fuel flow problem? but that's just a thoughts, probably works just fien for you.

Anyway, good luck man, I hope you get this figured out. I have chased my ass to know end for these types of sputtering and or back firing and coughing, finally once I got the above things taken care of....and a good map all seems to be running nicely.

keep us posted brother!!!

SWODude:

Here's step 3, from page 7-64 of the manual:

Service Manual:

3. Adjust:

• throttle position sensor angle

a. Disconnect the throttle position sensor coupler

from the throttle position sensor.

b. Connect the pocket tester (Ω × 1k) to the

throttle position sensor.

Positive tester probe → blue 1

Negative tester probe → black 2

c. Measure the throttle position sensor maximum

resistance.

d. Calculate the throttle position sensor maximum

resistance when the throttle is closed.

Throttle position sensor maximum

resistance (throttle is fully closed) =

Maximum resistance × (0.13 ~ 0.15)

 So am I missing something here?  If black BLUE  -black resistance should be constant, then why are they telling me in Step 3 that the resistance should be lower with the throttle closed?  And if my TPS were fine, then why do I get the sputter with abrupt throttle changes, especially when I hit bumps or potholes?  And no, I'm not getting any trouble codes or warning lights. 

The photos in my 1st reply have been edited with details of the procedure! Also, our manuals must differ as Item 3 is on page 7-67 of my manual

The shop manual is written-up as Items 1 - 3. Item 1 TPS on throttle body (TB), Item 2 TPS removed from TB & Item 3 Adjusting the TPS sensor angle with the throttle closed on TB!

Your current TPS max ohm is 5.6k ohm = 5.6 x 1000 (k) = 5600 ohm: 5600 x 0.13 = 728 and 5600 x 0.15 = 840

Your CURRENT TPS @ throttle closed should be adjusted to: 728 - 840 ohm @ T2 & T3

Your target for the above should be: 784 ohm with the current TPS, which is the mean/middle number. Just be sure to be within the tol

As stated above, this is a very sensitive adjustment and as you tighten the 2-tamper proof screws on the TPS you'll see what i mean.

Once again i suggest you connect your VOM to T2 & T3 and you'll see the variable resistance as you operate the shaft of the TPS from closed to open!

Your latest diagnosis is becoming dynamic now with bumps & potholes & i never asked about codes 

My .02 is that your TPS is fine but i've been wrong before .... GOOD LUCK

It coughs through the throttle bodies.  It's been doing this since the winter.  I've messed with all kinds of maps, but it always seems to do it in the 1500-2000 RPM range. 

Since it's mostly coughing through the TB's, I'm suspecting that I'm lean in this range. I'll work on tracing my wires and fuel lines later in the week.  Once I get the TPS on (which seems to be fine now that all of you have clarified the test procedure) and check the alignment of everything like the TB's, then I'll enrich my map for that range. 

Can any of this caughing/sputtering damage the internals of my engine?  

PS - I also noticed that my wire harness going to the TPS looks a tad different from the pics AlanH posted.  My yellow wire has a gray wire spliced into the yello TPS wire.  I think this might be some variation on the Perfect PCIII install.

My bike has been doing the exact same thing lately. I don't have a PCIII though. I just keep getting the little poof through the TB's at the 1900rpm area or just when I'm cruising at the 1900rpm range at low speed and I have the throttle in a neutral position. My bike has not had the TPS or CPS rexall done as you guys talk of. Is the recall on the TPS or CPS?