300xs

**wideglide55** · 03-18-2023, 10:54 AM

I have a freshly built 300XS Optimax from DBR, the Throttle position sensor fell apart and I replaced it.I am having surging at idle and idle is high after full throttle runs,can anyone tell me if the new sensor has to be calibrated or zeroed in the computer?

**25two.stroke** · 03-18-2023, 10:07 PM

On every key-up the ecm should read the tps and self-calibrate. Theres no calibration you can do. However, what you described sounds just like a bad tps on an optimax, so its possible yours just happens to be bad or the ecm is not reading it correctly.
Plug in a ddt or diagnostic laptop and look at the tps reading. Throttle up and down (engine doesn't need to be running) and look for smooth transitions. If it jumps around then its bad. Or if while the engine is idling you can touch the tps link rod gently and it revs then you also know its bad.

**wideglide55** · 03-18-2023, 11:09 PM

Originally Posted by 25two.stroke

On every key-up the ecm should read the tps and self-calibrate. Theres no calibration you can do. However, what you described sounds just like a bad tps on an optimax, so its possible yours just happens to be bad or the ecm is not reading it correctly.
Plug in a ddt or diagnostic laptop and look at the tps reading. Throttle up and down (engine doesn't need to be running) and look for smooth transitions. If it jumps around then its bad. Or if while the engine is idling you can touch the tps link rod gently and it revs then you also know its bad.

Ok thanks man,I will get my guy to plug it in and check it.It was fine for about 6 trips after I put the new one on and it just started acting up on the last trip I took.