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Discussion Starter · #1 ·
I have a 19 defender hd8 base with almost 16,000 miles. I've recently felt the machine start to feel it was cutting out or bogging down a small amount not really noticeable. Then last week it got worse and the check engine light came on, limped it back to the house, not far 1/4 mile at the most. Shut it off fan stayed on after the key was shut off like usual. Started it earlier this week and no check engine light and ran perfect. Started it later that day and the light cutting out or bogging down was back with no service engine light. One time I'll start it and it runs good next will bog down.
I've only owned this machine for about 4 months, ran fine for the first 3 months. Any ideas on what the issue may be or point me in a direction to look?
 

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You need to check actual fuel pressure. Also change plugs.

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Regular Joe
2014 Maverick 1000r
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What code(s) are ya getting?
 

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Yes the fuel pump can cause codes. Ive seen it have low enough pressure to cause a misfire code and an O2 sensor code.


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Discussion Starter · #10 ·
Well I finally got it to the dealer. Compression was 120 on both cylinders, they adjusted the valves and got the compression to 160 on both. Had the fuel pressure tested aswell, was reading 40 on the gauge. Installed a new fuel pump 52 psi now and a fresh oil change. Had them look everything else over, belt was good and so seems everything else.
Got it home and took off on my usual gravel road route, 10 miles or less. No higher than 30 mph, was being easy on it. Went to turn around and noticed it back firing (popping randomly). Acceleration and power is fine now so it seems but popping when I let off the gas. I called the dealer back and sent him a video of it popping. He questioned my fuel type and quality. It has fresh 87 oct pump gas in it. Dealer now says they're brainstorming. Waiting to hear from them now.
 

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Did they put spark plugs in it? Does it only pop at idle or all the time?

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Interesting, my almost 18000 miles defender started doing that also. I thought for sure plugs would fix it as they hadn't been done in a while and when my other defender started popping at idle and had a slight miss, plugs fixed it. But after throwing new plugs in this one it is still popping at idle. The old plugs looked awful. Not even sure how it was running honestly. Plan is to check valves and fuel pressure when I get a chance.

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Discussion Starter · #14 ·
Does anyone have timing specs or instructions for my situation? Looking for the timing marks on the (flywheel/magneto) in relation with each cylinder. All I can seem to find on the web is 1 and 1-2 but that is for older can am 800 motors. My flywheel has a S and C stamped on the notches, and neither line up with the marks on the timing chain gears.
 

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It is the same as the older can ams.


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Discussion Starter · #16 ·
Thanks. I got the valves set .006 exhaust..004 intake. Lines on pulleys were perfect on both cylinders. Took it for a cruise and it's still popping at a stop in gear or idling in park. 3-4 seconds between pops but seems louder now.
 

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Check your crankcase vent hose. Also check for intake leaks. Spray either ether or brake clean on the intake. Were it meats the head.

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Discussion Starter · #18 ·
Crankcase vent hose looks good, no visible melted places or separation from connections. Checked the intake connections with ether, used half a can or more spraying anywhere I thought could leak air, no change idle rpms. I'm clueless
 

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Regular Joe
2014 Maverick 1000r
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It just hit me your injector(s) might be getting lazy or some deposits built up, not sealing closed correctly, and leaking fuel into the combustion chamber when it's not wanted.

Have you pulled those and checked spray pattern and operation?
 
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