Post Throttle Body Synch Problem

[Icy1]

Looking for a little help . . .

Just syched the TBs using a Carbtune II and what a difference - I can feel the power difference. And SOOOOO smooth . . .

Problem is my fuel economy has dropped almost 25% (can the jokes about a heavy throttle hand taking advantage of the increase in power) and I can smell gas everytime I sit at idle. I had been running 40-42 MPG commuting (mixed interstate and street) now I'm lucky to hit 32. Went on a 400 mile trip this weekend - almost all highway and I took it nice and easy - and where I would normally expect 45-46 MPG I got 37!

Where's the gas goin' and why is it going there? I'm running a 2005 with PC III USB (no change in map since I bought the bike used 4k miles ago) 4-n-1 Akro. Changed the plugs at the same time - but went stayed with the OEM original (nice light toasty brown color on the 4 plugs I took out)

Thoughts?

 

[AzBooSa]

Did you reset the TPS? Could be the reason your running rich.

 

[Icy1]

(AzBooSa @ Nov. 19 2006,20:50) Did you reset the  TPS? Could be the reason your running rich.

Reset the TPS last night - smells better already!

Need to run a couple of hundred miles to check the fuel economy (sounds like a reasonable excuse to ride) and confirm the fix.

Thanks AzBooSa

 

[runeight]

Save me some time please. How did you reset the sensor?

I also have the Carb Tune and need to do this myself.

thank you..

runeight...

 

[Icy1]

(runeight @ Nov. 21 2006,10:16) Save me some time please. How did you reset the sensor?

I also have the Carb Tune and need to do this myself.

thank you..

runeight...

To set the "closed" throttle position

The Powercommander web site has a tutorial - but you need to have the unit on the bike, plug the unit into your laptop with powercommander running, start the bike, run at idle when warm, select "power commander tools" menu, "Set Throttle Position" click the arrow next to the right of the "Closed" window, click "OK"

But open the tutorial so you can see it done:
http://www.powercommander.com/tut_download.shtml

 

[8Daytona8]

Ok but did it fix your problem with waisted fuel? To set the TPS on a stock fuel sys find the 2 wire white plug L-side under your front or maybe rear seat, paper clip the two connectors, switch on! the ( - coo ) should be in the middle in info window on dash (thanks to a ORG member who knows his shid) setting it if the mark ain't in middle is another question

 

[Pipefighter248]

Pic below.
Not hard to do.
Just be sure, once you have it set right to hold while tightening, or it will throw it back off.

 

[8Daytona8]

After i did and redid my TB sync for the MPG dropping i have come to the conclusion zuki sets the two center cyl to idle lean and lags until the ecm kicks the fuel up at say 3800 rpm

Rhythm told me where to find my test connector and check it! It was in the middle like it should be. The eng idles much better and won't stall even @ 1k rpm idle. But MPG has gone down and when getting on it past a fellow rider they say they smell unburnt gas!

 

[Charlesbusa]

He reset the PC's TPS.

Not the bike's TPS.

 

[Icy1]

(Charlesbusa @ Jan. 18 2007,14:14) He reset the PC's TPS.

Not the bike's TPS.

Correct - that's what I get for doing my own work!

But the BIKE'S TPS is now reset - after half pulling off the undertail as some helpful individual (probably the dealer that installed the PCUSB) had the "dealer mode coupler" hidden UNDER the wiring harness on the left side of the bike.

The "special tool" (paper clip) worked fine - but where the service manual describes "2 screws" on the TPS, my 2005 has only 1 screw - but it did move the little bar into the center of the display.

Now do I have to reset the PCUSB TPS again before I try for a little better fuel economy?

 

[Icy1]

Epilog . . .

Still runnin' rich . . . . Still can't figure it out

So started again - open the bike, trace all the vacuum hoses using the service manual. Everything's in exactly the right place allowing for the blanked hose off TB#4 that would go to the PAIR system that was removed when the Akro exhaust was installed. Remember those words.

TOTAL FRUSTRATION - I figure the advice you guys have been giving CAN'T be that wrong.

Go over the vacuum hoses again. They're STILL in the right places.

Pure chance - notice a crack in one of the hoses right at the TB port. That hose that WOULD be connected to the PAIR system! (it's blanked off with a machine screw tightly in the open end and routed down and back through the clip that held it when it actually had a use.)

DUH!!!!!

Replace that hose and all the other vacuum hoses (because I'm paranoid and have enough hose to do it) - recheck the synch - it's fine (within 1")

Swap the hoses around on the CarbTuneII 'cuze I AM paranoid and tired of doing this and want to make sure they are in-synch. Synch still within 1"

Put the hoses and airbox back together, set the idle to 1150, reset the Throttle Position Sensor using the magic paperclip tool - centered.

Reset the PCUSBIII Throttle position.

1st tank - 39MPG (up from 31) in mixed city/interstate commuting traffic.

Had to be something - but seems like vacuum hoses should last longer than 10K miles and one synch. The hose that was cracked was sharply bent at the TB port - perhaps it was handled too roughly during the PAIR mod and finally gave up when I moved hoses to perform the synch.

Don't know, don't care - runs like a top - a very HIGH powered top.

 

[Pipefighter248]

Glad you got it figured out.

 

[Burger King]

Man, I learned 2 things today! I should be able to leave work and veg out for the rest of the day........

 

[Wag]

Glad you got it figured out!

And thanks for letting us know. Always good to know what the resolution to a problem is
--Wag--

 

[Icy1]

(Wag @ Feb. 03 2007,10:18) And thanks for letting us know. Always good to know what the resolution to a problem is
--Wag--

That's why I put it here - to give the next guy another place to look before he pulls out as much hair as I did.