Engine stalls at low idle / trouble restarting

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Tomato
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Engine stalls at low idle / trouble restarting

Post by Tomato »

Hello.

I figured to ask for a little advice before I try to service my pcx 125 (2011) engine and maybe make things more difficult then perhaps they may be.

I got 35000 miles on my bike. Generally I put regular (87 octane) and my engine is starting to give me issues. When I start my bike (cold) it runs for a about 20s and then more often then not the bike starts to misfire and starts to stall out if I don't actively open the throttle a little bit. It used to be just an issue in cold weather but now it seems to be happening more in hot weather as well. Additionally when I come to a stop such as a traffic light after the bike hasn't been in operation for a prolonged period of time the bike stalls and I have to restart or keep the throttle open just a smidge to keep the idle up and the engine from stalling. Sometimes after it's initially started and stalls the bike is rather troublesome to get started again and seems to buck a little and makes wierd noises.

Also sometimes when I throttle up from a stop the bike accelerates, momentarily pauses, and then continues to accelerate. It's getting to the point where I can't put this off anymore as I feel that this behaviour is becoming dangerous.

At this point I've tried a few injector cleaners, putting 93 octane in it, replaced the spark plug, cleaned out the air filter,
and changed the oil. I don't think the drive oil is an issue but even checked that as well. The drive belt is in good condition as well.

I plan to check the fuel pump & filter but I suspect since i've had the bike almost ten years that their may be some kind of issue... maybe carbon buildup attributing to this behaviour..

Anyone ever dealt with this kind of behaviour and maybe have some advice or products to recommend? I was thinking of getting one of those concentrated fuel system cleaners and using that as well.. I'm a little unsure if those are safe as they are intended for cars though.

Thanks!
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Re: Engine stalls at low idle / trouble restarting

Post by you you »

I think I’d be checking out the valve clearance next.
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Re: Engine stalls at low idle / trouble restarting

Post by springer1 »

I'd try adding some Lucas Fuel Injector cleaner to the fuel; any auto parts store sells it. I once thought this stuff was snake oil, but have learned it works. Not saying it will absolutely solve your problem, but it's a cheap step to take and check off. It even worked on my 15 year old lawnmower with a sticky float. Don't over mix it too much - & keep running with it for awhile.
Tomato
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Re: Engine stalls at low idle / trouble restarting

Post by Tomato »

Thanks for the input. Both sound like good ideas.

I'm thinking of trying to take out the throttle body(crosses fingers) and clean that and the iacv valve. I found a YouTube video on how to clean the throttle of a Honda accord.. Seems to have same basic function with the iacv valve.. just designed differently.. the symptoms for the problem seem to fit though and the repair manual checklist leads me in that direction too. Will sit with the repair manual nice and sober tomorrow.. I really like the damn thing.. The body cover has pros and cons to it.

After that I will check the clearance and once I get an dle I don't have to babysit I'll let it run with some detergent on the center kick for an hour or two.
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