TROUBLESHOOTING AN OLDER UTV
My mom has a 2004 Polaris Ranger 700 twin. It won’t start unless you hold the gas pedal about halfway down. Then it will start and idles at about 450 to 500 rpms, but after about 30 seconds, it dies. If you start it and just put it in gear and go, it does fine until you try to idle. I changed spark plugs but made no difference.
I wonder if the injectors aren’t working right. It has plenty of fuel because it has pressure in the pressure valve. It will actually leak a little so I have a valve cap on it. What steps should be next? Thanks a ton!
Well, Duane, I think we can solve your mother’s idle problem. On the intake manifold, there are 2 sensors. One is a Throttle Position Sensor (TPS) and the other is a Temperature and Barometric Pressure Sensor (T-BAP). The TPS can get water in it and that screws with the idle speed and the T-BAP has a history of wires breaking inside the wire casing as well as with the TPS sensor too. If it turns out the sensors are not the problem, I would suggest covering the bottom of the fuel tank with heat reflective foil and install a Fuel Pump Factory replacement pump. (https://www.fuelpumpfactory.com/Fuel-pump-Factory-Polaris-Ranger-replacement-500-7-p/cnt-ran-03.htm). The OEM fuel pump may be weak and or the engine heat is boiling the fuel in the tank, causing the fuel pump to either fail or pump a reduced amount of fuel to the injectors, causing a lean mixture at idle. Also have a look at the fuel strainer located on the OEM fuel pump to see if it is plugged. Note the pump from the Fuel Pump Factory comes with an upgraded fuel strainer.
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