Just wondering which is the best to use, and what are the reasons for each?

 

FD only has one tps?

And FC, both tps units are narrow band.

 

Mmm.....Actualy the Fd has wide range and narrow range outputs. See Page F182 of the service manual.

 

The narrow range output gives a lot of resolution at low throttle angles but stops reading above a certain throttle angle. The service manual shows a diagram of approximate voltage vs. throttle position, it may be the same page as mentioned above. I'd go with the wide range output.

 

Ah ok. Did not know that. Nice one.

 

Wide range.

 

Wide range is fine. On the s5 FC there are physically two plunger-type TPS's, one for full and one for narrow range. The FD has a "slider" design similar to what is used on Toyotas of that era. It producers both narrow and full signals in one integrated unit. It's a much more reliable design than the FC sensor.

 

+1 The earlier reference to both being narrow range is incorrect.

 

NO its not INCORRECT.

I have tested BOTH UNITS and they are both narrow band units.

YOU are BOTH INCORRECT IN SAYING THAT THE S5 is wide range. Actually tested both of them on a haltech ecu as well.

 

Might want to test again. Or maybe read a service manual? The short range sensor reads linearly to approximately 30% throttle angle at which point the actuating arm comes completely off the sensor and the sensor goes wide open. This is the same arrangement as the S4 throttle sensor. If you wire these sensors to an engine management system you get a linear response at less than ~ 30% throttle. Any more throttle angle and the reading goes wide open. This arrangement will generally work but is not ideal.

The full range sensor on the S5 is actuated by a cam that maintains contact with the sensor "button" through out the range of throttle angle; 0-100%. This sensor will read actual throttle angle through out the entire range of throttle travel.

Perhaps the sensor you tested was faulty, with a dead spot that made it seem as though it wasn't working properly? Perhaps I've gotten extremely lucky with the S5s I've setup and somehow managed to obtain a linear, full range output from the sensor you say is not a full range sensor?

 

Well i have plenty of s5 tps units here.

I will test another unit. And see if its full range.

Last one i checked was not linear accross the whole range.