4stroke cdi unit for f100a

[saxplayer]

Hi people.
new to the site so not sure how many people are here from the Uk. looking for some advice and possible parts.
The port engine runs uneven on tickover, but all else is good. 43knots at 6000rpm.
i have investigated and found i have no voltage to the throttle position sensor,( engine is carbed). Ime putting this down to a faulty cdi unit.
Could it be a fault somewhere els? If not, where can i obtain one from?
My local Yamaha dealer in Plymouth qouted me £400 for a replacement prop, so there is no way ime knocking on his door!!!!!
Cheers all
shaun

[boats.net]

Might check continuity on wires in harness before replacing CDI unit to make sure not just a bad wire.
Not sure if US model uses same CDI or not but here is link to a 2003 F100,
2003 F100TLRB Yamaha Outboard Parts

[jetmech68]

There should be "No" voltage going to the throttle position sensor. The TPS is basically a calibrated rheostat that sends a resistance reading to the ECM, which in turn translates the reading to a "throttle plate position", and adjusts timing and fuel flow to meet demand. I'd clean the carbs before I went down the CDI road.