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Polaris side by side ECU and harness upgrade

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This is my 2011 Polaris Ranger 800. This has been an awesome machine and has taken me places off-road I probably never should have been! Unfortunatly it has had some issues since new and only gotten worse over time.

Short video 2011 Polaris Ranger 800


1.) TPS wiring: This 800cc engine is not a smooth running engine. Due to the vibrations particular parts of the wiring harness have been known to suffer from broken wires. Polaris tried zip-tieing the wires in all sorts of ways but given the design and build of the harness it's a futile attempt.

2.) No known way to trouble shoot or tune the EFI system. This is made obvious once you start having issues with the TPS and inconsistent idle rpm's. You are left probing the sensor and physically adjusting the throttle blade to get the voltage with-in specification rather than setting the throttle where it belongs and adjusting the parameters.

3.) I feel the manufacturer has left a lot of performance on the table. This particular year engine has a rather robust array of sensor that could be leveraged to pull the most from the engine.

Project goal:

1.) Remove and replace the factory ecu with a aftermarket unit that will allow me complete control.

2.) Design and build a new wiring harness that corrects the factory shortcomings.

3.) Design or procure a higher quality throttle body.

This machine is going to be my testbed for my future business. I have been a CAD operator / Detailer since 1998 with a Machinist background. I recently suffered an "Eye stroke" in my left eye causing me to lose vision in that eye. Now days I have to take a lot of breaks from the monitors as my one good eye gets strained and negatively affects my productivity. Therefore I am going to attempt to start my own small business, designing and producing parts for the off-road community. I already own this machine and know all of it's downfalls.

I joined HP Academy many moons ago with the intention to learn engine management tuning for my race vehicles.

I guess I will start with what sensors are present in stock configuration.

TPS / T-map / TPS / Cam phase sensor / speed sensor / IAC / EPS (electric power steering)

fuel pump / stator / regulator

parking brake / brake line pressure / front differential lock / rear differential lock

I have not thought about the EPS and which aftermarket ECU offer EPS management. The factory ECU uses the speed sensor to regulate the power steering assist. It's a common issue to damage the speed sensor and the steering light come on.

At minimum with this project I want to build a new harness using quality wire and better harness routing.

I want to share more pictures but having difficulties.