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Discussion Starter · #1 ·
My very reliable 2014 XP1K’s engine suddenly died recently like the ignition was turned off. Once stopped rolling and in park, it would crank normaly, but not fire. Everything electrical had power, just would not fire. After about 10 minutes sitting, I got it to start normally and operate for another 8-10 miles before repeating this process. Died five times over the 50 miles back to the trailer.

Have tested resistance in coil and spark plug wires, plus the crank position sensor; all in spec. Fuel pump tests normal, tank and filter look very clean.

Starting to look towards EFI and Fuel relays.

Anybody have a similar experience, or any troubleshooting tips?
 

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Possible fuel pump/vapor lock issue, try loosening the gas cap and firing it up right away when it dies.

Also Not on a razor but 2 similar instances. Once on an 89 Camaro, dealership started throwing parts, fuel filter & Pump, then fuel regulator. Wound up being the distributor. Few years later on a sled 96 96 Arctic Cat ZRT, did the same thing when the stator started going out. That's probably where I would start is with the stator and ignition. Somethings overheating. maybe stator or fuel pump.
 

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Discussion Starter · #3 ·
Thanx Fosgate! I've never heard of vapor lock on a fuel injected modern engine, but that will be easy to check next time.

I'm preparing test equipment to go out and try to replicate the condition so I can see what all is not operational when attempting restart. Want to be able to quickly probe for voltage at fuel pump and primary side of the coil, check for spark on secondary side of coil, check for fuel pressure on the rail.
 

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We had one unit a couple weeks ago riding with us that was acting up when it got under 1/2 tank. It was over 100f out and had to keep popping the gas cap until we could get to a gas station and top it off. Would run fine until we got below 1/2 again. Guess it was something with the pump on that one.
 

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Discussion Starter · #5 ·
That's a new one for me. I'll have to remember that trick with the fuel cap. Don't think it's too easy to get to the fuel tank vent on the trail. I appreciate the help!
 

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Positioning sensor from cam or crank? May or may not throw a transient code. After refiring code would go away and it would run good, possibly even die randomly and need to wait to be restarted. It would also be more likely happen when the engine is warm.
 

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Years ago I had an MGB that would stop suddenly and after sitting like you say around 10 it would start right up after much trouble it turned out to be a solid state control module that when the resin block heated up it expanded and caused the wiring to separate until it cooled down. Switched to manual ignition and never had the problem again. Just something to consider.
 

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Discussion Starter · #8 ·
Positioning sensor from cam or crank? May or may not throw a transient code. After refiring code would go away and it would run good, possibly even die randomly and need to wait to be restarted. It would also be more likely happen when the engine is warm.
Yes, I've tested resistance on the CPS (cold), and will have to keep an eye on that. Not sure what a faulty CPS would cause the ECU to do? Just a guess the ECU would kill power to the EFI relay??
 

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Discussion Starter · #9 ·
Years ago I had an MGB that would stop suddenly and after sitting like you say around 10 it would start right up after much trouble it turned out to be a solid state control module that when the resin block heated up it expanded and caused the wiring to separate until it cooled down. Switched to manual ignition and never had the problem again. Just something to consider.
Was thinking that the ignition coil could be having that same trouble. When I go to recreate the problem, I'll be checking for power at the coil on both the primary and secondary sides. If the coil is failing due to heat, I should still see voltage on the primary side of the coil, but not the secondary.
 

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Was thinking that the ignition coil could be having that same trouble. When I go to recreate the problem, I'll be checking for power at the coil on both the primary and secondary sides. If the coil is failing due to heat, I should still see voltage on the primary side of the coil, but not the secondary.
Very good possibility. Over on the sled side of things some of the new RMK 950 Boosts are experiencing odd stuff with coil packs on sleds new out of the box. Swap them with a known good and they run like raped ape.
 

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Yes, I've tested resistance on the CPS (cold), and will have to keep an eye on that. Not sure what a faulty CPS would cause the ECU to do? Just a guess the ECU would kill power to the EFI relay??
Yeah I'm not sure what happens or why. I've seen bad CPS cause a machine to fire normally when it's cool, but when it's hot if you try to restart it, it just cranks. And only about 15% of the time you could get it to start hot. Check it cold and hot(if possible) and see if there is a difference. Could be a short somewhere
 

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Discussion Starter · #12 ·
Very good possibility. Over on the sled side of things some of the new RMK 950 Boosts are experiencing odd stuff with coil packs on sleds new out of the box. Swap them with a known good and they run like raped ape.
So far, everything I've looked at is pointing to the ignition coil itself, or the ECU's ability to fire the coil. Hope to able to recreate the problem within the next few days and see where that leads me.
 

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Discussion Starter · #13 ·
Yeah I'm not sure what happens or why. I've seen bad CPS cause a machine to fire normally when it's cool, but when it's hot if you try to restart it, it just cranks. And only about 15% of the time you could get it to start hot. Check it cold and hot(if possible) and see if there is a difference. Could be a short somewhere
I've tested the CPS for the normal resistance cold. Do you know how to test it hot other than that same resistance test? Would like to determine if it's sending the same signal when the engine won't start.
 

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Discussion Starter · #16 ·
Update on RZR engine quitting:

After replacing the coil, I've installed a new AGM battery (which I was due for anyway). I've also checked wire looms for excessive resistance/shorts in the coil and CPS circuits. Checked all connections at the ECU and at all main sensors. Still having the engine cut out and briefly backfire, intermittently. On a 91 degree day here in SW Idaho, it took me 43 miles of pavement driving around our area (flat, no hills) before the engine problems started again. So the engine seems to need to be good and hot before this problem occurs. Coolant temp seems normal at between 177 and 186 on flat terrain with 91 degrees ambient; so the engine isn't overheating, but the engine area does seem to get good and hot in order for this problem to surface.

Interestingly, I took out our 2012 Teryx 4 this past sunday since I didn't trust the RZR yet, and after a half day's riding, started experiencing similar issues with power cutting out at a particular throttle position and engine load. Not exactly the same issues as the RZR, but strangely similar. The only things consistant between these two UTV's is the fuel I use (premium E10) and the fuel stabilizer I put in the tanks/engines during the winter months.

So now I'm going to start a thorough inspection and cleaning of the fuel system on the RZR (and then the T4) to make sure I don't have any strange fuel issues that could be causing my cutting out problems. Also going to switch to Ethanol Free gas that's available here locally. Hope I'm getting closer to finding this problem...

Thanks to everyone for their input!
 
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