There are several things that will cause a hard, cold start on your Polaris.
Let’s go over the steps to diagnose this problem. It comes about by a process of elimination:
Battery connections, including dirty or loose connectors. Clean and service battery and tighten terminals.
Check battery connections and test battery. Loose battery connections or corroded battery connections can make the UTV lose communication briefly and cause multiple problems.
Battery not holding a load might make the engine turn over too slow or not have the required voltage to run all the electrical it takes to start the engine up.
Pull diagnostic codes and see if any current engine codes or history codes have been stored. If codes are present or there are history codes, pull the diagnostics on these particular codes and determine if this is something that would tie into the hard start conditions.
The main sensors I am looking for in a cold start are:
- T-Map Sensor
- Temperature Sensor
Fuel volatility test – siphon some fuel out of the tank into a plastic bottle and check for smell and discoloring of fuel, and make sure there is no water inside the fuel.
Fuel pressure test:
Get your particular fuel pressure specifications from the service manual for your exact UTV. If there is a fuel service port on the fuel rail, it works best for testing fuel pressure.
If there is not a fuel test port, the next step is to remove the fuel pressure line right off the fuel pump assembly. Make sure to remove the electrical connection first, and know that the fuel line may have some pressure in the line. So, always have rags ready and no flames or any way to cause a spark.
After removing the fuel hose connection, hook up your fuel pressure gauge, and then connect the wiring to the pump. When you test pressure, just turn the key on – you do not need to start the engine.
Pressure should immediately jump up to the specified pressure when the key is released, it might lose a couple of pounds, but then hold steady.
If all the above checks out in spec, install your lines back on to the fuel pump. Then test for leaks and head to the next step.
Valve adjustment check and engine compression:
If you have an engine compression tester, run a compression test on your engine and note.
Then remove your valve cover and drive belt cover to turn your engine over, so you can get your valves in the correct positions to check your valve clearance.
Checking valve clearance is one of the most overlooked and underperformed services on your Side x Side and one that could cause a lot of problems and check engine codes to come up.
Your specific measurements will be in the factory service manual on your particular UTV. Just know that I have found several mistakes on what is printed in a manual, so double-check different places to make sure this sounds like the correct clearance.
For example, in the 2014-2015 Polaris XP1000 factory service manual it calls for .006 intake and .008 exhaust clearance. But, if you scroll down to the chart for replacing the pucks, it thinks the starting clearance on your exhaust is different than the actual clearance spec.
If you need to change the pucks to get your valve clearance correct, do the math on a piece of paper and then order the puck numbers through the dealer.
After you adjust your valve clearance to the correct tolerance, take another compression test and notice the jump in engine compression.
Valve adjustment can be a big jump in your horsepower if your engine had out of spec valve clearance.
For more information on this topic please visit my YouTube video at:
Until we ride again
The post How to Diagnose Engine Cold Start on 2017 Polaris General 1000 first appeared on UTV ATV Repair.
The post How to Diagnose Engine Cold Start on 2017 Polaris General 1000 appeared first on UTV ATV Repair.