I have an 08 Grizzly 700 I'm working on. The guy told me that it was running, he shut it off and went inside. When he came back out, it started up but started sputtering and died. He couldn't get it started again.
I have checked EVERYTHING: fuel pump is 40psi steady. throttle position sensor checks out. air pressure sensor checks out. intake air temp sensor checks out. fuel injector fires - even tried replacing it. valve clearance is right. timing is right. spark plug fires hot. wiring from the ecu to everywhere checks out. voltage and ground to the ecu is good. The ONLY thing I find off is compression. The manual calls for 74 max and we have about a hundred. I can't think that that would keep this from running though. I was told elsewhere that it sounded like the ECU, but I cannot convince this guy to spend hundreds of dollars on an ECU that may or may not be the issue. Since this is trying to start, though, I have my doubts about that, too.
It spins, fires and tries to run but just can't keep running. In the little bit of time that it does try to run, it's carbon fouling the plug as if it's getting too much fuel. Odd thing, though is that if I try to choke it by putting my hand over the throttle body intake, it actually tries to run better, even though it still can't. One more thing is that if I crack the throttle butterfly open even the slightest bit, it won't even try to start.
I am hoping for a second opinion before I have to give up. Any and all help is going to be greatly appreciated.
I have checked EVERYTHING: fuel pump is 40psi steady. throttle position sensor checks out. air pressure sensor checks out. intake air temp sensor checks out. fuel injector fires - even tried replacing it. valve clearance is right. timing is right. spark plug fires hot. wiring from the ecu to everywhere checks out. voltage and ground to the ecu is good. The ONLY thing I find off is compression. The manual calls for 74 max and we have about a hundred. I can't think that that would keep this from running though. I was told elsewhere that it sounded like the ECU, but I cannot convince this guy to spend hundreds of dollars on an ECU that may or may not be the issue. Since this is trying to start, though, I have my doubts about that, too.
It spins, fires and tries to run but just can't keep running. In the little bit of time that it does try to run, it's carbon fouling the plug as if it's getting too much fuel. Odd thing, though is that if I try to choke it by putting my hand over the throttle body intake, it actually tries to run better, even though it still can't. One more thing is that if I crack the throttle butterfly open even the slightest bit, it won't even try to start.
I am hoping for a second opinion before I have to give up. Any and all help is going to be greatly appreciated.
