'98 V11EV Throttle Position Sensor

[n3303j]

Last season I re-read all the info on synching throttle bodies and setting throttle position sensor correctly.

I went through the procedure and the bike has been running well ever since (wasn't bad before). I did have a lot of fun with all the details and was pleased with what I have learned.

But I have never been thrilled with the fuel consumption on this bike coupled with its small tank. Son-in-law remarked that it smelled like it was running a bit rich.

I figured that the TPS tells the control unit how wide the butterfly is open. The control unit adds the proper amount of fuel to work with that figure. The higher the voltage the more fuel delivered at each cycle.

So if I were to set the TPS voltage a bit lower than the standard number, the control unit would be delivering a bit less fuel at every throttle position. Therefore I would effectively lean the mixture over the whole throttle range.

Anyone done this with positive results? Any reason I shouldn't try? Hot run / ignition chop / plug inspect a good way to judge mixture at speed?

Thanks

[fotoguzzi]

I think your problem might be in the fuel trim setting...

Have you tinkered with the trim dial that's on the side of the computer box? (Under a rubber plug)  It's said to trim the fuel amount at idle but I found it altered how the motor ran further up the rev range.
That dial has a range of maybe 2 revolutions each direction then it has no effect and can even become disconnected so don't dial it too far.
If you do any adjustment to it take a ride of 10 minutes or so, I think the CPU has to learn the new setting? On one of my 98's I turned the dial pretty much cause it didn't seem to change anything then went on a ride and after a few minutes ran horrible, all rough and cutting out, I think it even died.. took me awhile to discover the dial was the cause.. so, turn at your own risk and only about a quarter or half turn at a time.
This on the p8 cpu in the 98 EV, after that (99 Bassa, 2000 EV with the 5m the trim is set with computer via guzzidiag or techno research software.
 I think the FI supplement manual tells which direction to dial for a leaner mix.. I don't remember. now, that was probably 9 or 10 years ago.
If you had a Co  reader you could know just what the mixture is while idling.

[JoeB]

[quote author=fotoguzzi link=topic=101542.msg1605741#msg1605741 date=1561261378
 I think the FI supplement manual tells which direction to dial for a leaner mix.. I don't remember. now, that was probably 9 or 10 years ago.
[/quote]

"Turning the screw clockwise leans the idle mixture"
https://dpguzzi.com/efiman.pdf
I marked it on the box so I'd know when adjusting it. LOL I don't remember things easily.

[flower_king001]

Been thru the same....

1. check plugs
2. check air-filter. IMHO a K & N flows better than the stock paper
3. If still carbon plugs adjust fuel trim. Clockwise > lean Counter Clockwise > rich

Even after all this I still get in the mid 30's on the highway with my 1998 EV. Running between 75 and 80 mph

[John A]

Use a non metallic screw driver or put some heat shrink on the shank or be careful to not short anything with the screwdriver , I'm led to believe the ECU  can be damaged that way.

[John A]

http://ca-cycleworks.com/efi.html
Maybe one of these TPIs is the right one. Prices seem decent,  someone here posted this link a few years ago and I saved it.

[flower_king001]

http://ca-cycleworks.com/efi.html
Maybe one of these TPIs is the right one. Prices seem decent,  someone here posted this link a few years ago and I saved it.

Yes, PFC3 works fine on a 1998 EV as I have been running one.

http://ca-cycleworks.com/pf3c.html